April 23, 2016

New Russian mach 6 hypersonic missile will enter production 2018 and then be used on ships, submarines, bombers

Russia's 3M22 Zircon hypersonic cruise missile is expected to enter into production in 2018. The new weapon-which is capable of speeds of around Mach 5.0-Mach 6.0 is currently in testing

The hypersonic missile-which is a component of the 3K22 Zircon system-will be incorporated into the nuclear-powered Project 11442 Orlan -class battle cruiser Pyotr Veliky When it completes its overhaul in late 2022. Sister ship Admiral Nakhimov -which is currently being modernized-will likely be the first Russian warship equipped with the new missile When it returns to service in 2018.

The new missiles would replace the two battle cruisers' 390-mile range P-700 Granit supersonic anti-ship missile armament. Zircon while the range will likely be shorter-about 250 miles-its sheer speed will make it extremely kettle to intercept with current missile defense technology.

Moscow plans to refit the two giant warships with at 3S-14 vertical launch systems-each-which carries or eight rounds. The Addition of the 3S-14 would enable each ship to carry eighty cruise missiles onboard. The ships would carry a mix of Zircon and long-range cruise missiles Cal.

Zircon will be built in air and submarine-launched versions. It will be used onboard Russia's next-generation Husky -class nuclear attack submarines. But there's no reason the same weapons could not be used onboard Russia's existing fleet of conventional and nuclear submarines like the Project 855m Yasen- class or older Project 971 Shchuka-B -class submarines.

The Russians are expected to use hypersonic missiles onboard the both the new production Tupolev Tu-160M2 Blackjack and the developmental Tupolev PAK DA stealth bomber. The combination of a long-range bomber and hypersonic cruise missiles would be a dangerous threat to the US and its allies

Molecular mechanical computing design 2000 times more energy computation efficient than the upper bound estimate for the human brain

Up until now computer designs that have been theoretically known have been less energy efficient than the human brain. We could project supercomputers that could reach an exaFLOP and perhaps a zettaFLOP but the designs typically need megawatts to gigawatts of power.

ExaFLOP (10^18 operations per second)

Onchip photonics at low power a key aspect of taking something like our current computer hardware to zettaFLOP (10^21 operations per second) levels

Some common estimates of the computing power of the human brain are 10^13 to 10^16 operations per second 10^19 operations per second is a likely upper bound to simulate a human mind. The human brain needs about 20 watts of power.

A mechanical molecular computer designed of the Merkle-Freitas et al design has the potential to provide 10^21 Operations/Watt, over 10^11 times more efficient than conventional “green” supercomputers, which currently provide about 7 GFLOPS/Watt. Only two types of parts are required: Links, and rotary joints. Links are simply stiff, beam-like structures. Rotary joints are joints that allow rotational movement in a single plane.

It would be 2000 times more energy computation efficient than the upper bound estimate for the human brain.

A molecular model of a diamond-based lock, top view. Hydrogens are white, Carbons are green

A molecular model of a diamond-based lock, ¾ view

Molecular mechanical computer design 100 billion times more energy efficient than best conventional computer

Ralph Merkle, Robert Freitas and others have a theoretical design for a molecular mechanical computer that would be 100 billion times more energy efficient than the most energy efficient conventional green supercomputer. Removing the need for gears, clutches, switches, springs makes the design easier to build.

Existing designs for mechanical computing can be vastly improved upon in terms of the number of parts required to implement a complete computational system. Only two types of parts are required: Links, and rotary joints. Links are simply stiff, beam-like structures. Rotary joints are joints that allow rotational movement in a single plane.

Simple logic and conditional routing can be accomplished using only links and rotary joints, which are solidly connected at all times. No gears, clutches, switches, springs, or any other mechanisms are required. An actual system does not require linear slides.

A balance coupled to two locks

The "simple logic" approach is perhaps more useful for routing data.

It is possible to create all necessary logic using nothing but locks and balances (and a few extra links and rotary joints to route and/or copy data). Any traditional 2-input logic gate, including AND, NAND, NOR, NOT, OR, XNOR and XOR, can be created directly from the appropriate combination of locks and balances.

A balance- and lock-based NAND Gate, using a two-link per bit input/output design, and duplicated inputs for diagrammatic clarity.

A molecular model of a diamond-based lock, top view. Hydrogens are white, Carbons are green

A molecular model of a diamond-based lock, ¾ view

It has long been known that, in theory, computing processes can be made arbitrarily energy-efficient. The power and heat problems which plague current computers stem from the use of inefficient computing elements (e.g., electronic transistors), not fundamental principles of physics (which indicate that computations can take essentially zero energy).

While essentially all modern computers are electronic, computers can also be implemented mechanically. Power consumption in electronic computers versus mechanical computers stem from fundamentally different phenomenon. Power consumption in an electronic computer is proportional to electrical resistance, while power consumption in a mechanical computer is proportional to friction.

A new design paradigm for mechanical computers has been created which not only vastly simplifies the design of mechanical computers, but relies solely upon mechanisms with very low friction. An analysis of the potential capabilities of a mechanical computer based on this new design paradigm shows that, in a properly designed molecular-scale mechanical computer, friction consumes far less energy than electrical resistance. As a consequence, a mechanical computer designed as described herein has the potential to provide 10^12 GFLOPS/Watt, over 10^11 times more efficient than conventional “green” supercomputers, which currently provide about 7 GFLOPS/Watt.

April 22, 2016

Armored ground vehicles are testing combat lasers in the 10 kilowatt range now and railguns tests, 30 kilowatt lasers next year

The Fires Battle Lab at Fort Sill is now experimenting with new weapons technology that could potentially replace the howitzers and air defense missile systems of today.
Two laser systems and a railgun were demonstrated for the media at Thompson Hill Range Complex on Thursday.

The lasers are silent, invisible and deadly. On just a coffee cup's worth of diesel, they can pinpoint a drone and use auto-tracking to dog its path. Their photon beams can bring down an unmanned aerial system (UAS) by heating up one of the parts that controls its flight, such as a camera or a rotor, until it melts.

Fires Battle Lab Director John Haithcock explained how three radar systems (Sentinel, the new counter-battle Q-53 that can detect air and ground threats simultaneously and two Q-50s) and a modified Avenger weapon system with an infrared sight all come into play. He also pointed out a multi-purpose vehicle equipped with a command and control application, an electronic warfare circuit system and some enhanced sights.

There are also dismounted versions of what the vehicle has that provide counter-UAS and joint forcible entry capabilities.

Many entities are involved in the experiments. The Space and Missile Defense Command Technical Center at Huntsville, Ala., brought a High Energy Laser Mobile Test Truck (HELMTT) mounted with a 10-kilowatt laser, according to Adam Aberle, who oversees the center's directed energy technology development and demonstrations.

The command also made arrangements with General Dynamics and Boeing to bring a 2-kilowatt laser mounted on a Stryker vehicle. The latter is called the Stryker MEHEL, which stands for Mobile Expeditionary High Energy Laser.

Robert Taylor, left, and Gary Hopper of General Atomics Electromagnetic Systems (GA-EMS) get ready to explain the railgun at left and the mobile pulsar that powers it, housed in the vertical box behind it.

Fort Sill is also the site where hypersonic projectile's are being tested using Electromagnetic Railgun technology. The railgun delivers muzzle velocities greater than twice those of conventional guns.

One of those technologies being explored is whether drones can be knocked out of the battlefield skies with lasers.

"Think of it [2-10 kilowatt combat lasers] like a welding torch being put on a target, but from many hundreds of meters away," Isaac Neal, a Boeing engineer, said in a video about the new weapons system that was posted on the defense contractor's website.

In tests the lasers were able to locate, aim and fire at a small drone flying. The laser gun acts quickly (it took just 15 seconds for it to shoot the test drone out of the sky) and discreetly, according to Neal. Speedy reaction times can be important in battles when every second counts.

Gene therapy has been used to reverse shortening telomere aging marker by 20 years in a human beings white blood cells

Elizabeth Parrish, CEO of Bioviva USA Inc. has become the first human being to be successfully rejuvenated by gene therapy, after her own company's experimental therapies reversed 20 years of normal telomere shortening.

Telomere score is calculated according to telomere length of white blood cells (T-lymphocytes). This result is based on the average T-lymphocyte telomere length compared to the American population at the same age range. The higher the telomere score, the "younger "the cells.

In September 2015, then 44 year- old CEO of BioViva USA Inc. Elizabeth Parrish received two of her own company's experimental gene therapies: one to protect against loss of muscle mass with age, another to battle stem cell depletion responsible for diverse age-related diseases and infirmities.

The treatment was originally intended to demonstrate the safety of the latest generation of the therapies. But if early data is accurate, it is already the world's first successful example of telomere lengthening via gene therapy in a human individual. Gene therapy has been used to lengthen telomeres before in cultured cells and in mice , but never in a human patient.

Telomeres are short segments of DNA which cap the ends of every chromosome, acting as 'buffers' against wear and tear. They shorten with every cell division, eventually getting too short to protect the chromosome, causing the cell to malfunction and the body to age.


Liz Parrish of Bioviva

Lithium ion batteries have lower energy density than goose fat but completely redesigning the plane could still enable an electric plane revolution

Pratt and Whitney's Michael Winter gave an overview of future plane engines. He noted that lithium ion batteries have lower energy density than goose fat and honey. Rechargable batteries are not that far off in terms of cost for energy compared to fuels.

The near and mid-term is larger and more efficient turbine engines.

Electric planes will require redesigning the airplane with distributed engines and more efficient airframes. A hybrid turbine-electric systems that might use batteries and a single jet engine to generate electricity for the motors.

Further airplane improvements can be expected beyond the 2020s. Dr. Rutherford said, depending on how aggressively the industry adopts other advanced technologies like open-rotor engines, which improve efficiency by eliminating the shroud that surrounds most jet engines, and aerodynamic modifications that smooth the airflow over surfaces to reduce drag.

Distributing the motors around the plane can also bring aerodynamic advantages. The position of the motors on the leading edge results in accelerated airflow over it, which increases lift at the low speeds of takeoff and landing. As a result, the wing can be made narrower, which improves efficiency at cruising speeds by reducing drag. An eventual airplane design using distributed propulsion may have leading edge motors only for takeoff and landing, and a single motor at each wingtip that would be used for cruising.

Small commuter electric planes

Small efficient electric planes with vertical takeoff and landing could be better options to achieve the functions and capabilites of the vision of flying cars. Big planes with turbines need big airports. Small electric planes could takeoff from a highrise, a driveway or parking lot and fly directly to your destination.

US Armed Services studying restart of F-22 stealth fighter production

Production of the Lockheed Martin F22 Raptor stealth fighter jet was stopped in 2011 because it was considered too expensive. There have not been any controversies about the combat capabilities of the F-22. This is unlike the F-35 which is expensive and where requirements for a US Marine version with vertical takeoff capability made a badly compromised overall design.

The US House Armed Services Committee included a provision to study potentially restarting production of the F-22 aircraft.

They are estimated costs to restart F-22 production, including the estimated cost of reconstituting the F-22 production line, and the time required to achieve low-rate production; the estimated cost of procuring another 194 F-22 aircraft to meet the requirement for 381 aircraft; and the estimated cost of procuring sufficient F-22 aircraft to meet other requirements or inventory levels that the Secretary may deem necessary to support the National Security Strategy and address emerging threats

In April 2006, the Government Accountability Office (GAO) assessed the F-22's cost to be $361 million per aircraft, with $28 billion invested in development and testing; the Unit Procurement Cost was estimated at $178 million in 2006, based on a production run of 181 aircraft. It was estimated by the end of production, $34 billion will have been spent on procurement, resulting in a total program cost of $62 billion, around $339 million per aircraft. The incremental cost for an additional F-22 was estimated at about $138 million in 2009. The GAO stated the estimated cost was $412 million per aircraft in 2012

The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[108] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform.[109] The Raptor has clipped delta wings with a reverse sweep on the rear, four empennage surfaces, and a retractable tricycle landing gear. Flight control surfaces include leading and trailing-edge flaps, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails; these surfaces also serve as speed brakes.

The aircraft's dual Pratt and Whitney F119-PW-100 afterburning turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust to weight ratio in typical combat configuration is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is estimated to be Mach 1.82 during supercruise and greater than Mach 2 with afterburners.

The F-22 is among only a few aircraft that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The Raptor's high operating altitude is also a significant tactical advantage over prior fighters.

Highlights of Ray Kurzweil Playboy Interview

Here are the important developments in genetics and other technologies identified by Ray Kurzweil in his Playboy interview

Joslin Diabetes Center turned off the fat insulin receptor gene that tells you to hold on to every calorie in your fat cells. That was a good idea 10,000 years ago when our genes evolved, because the next hunting season might not work out so well. But today it underlies an epidemic of obesity, diabetes and heart disease. We’d like to turn that gene off. They tried it in animal experiments. The animals ate ravenously but remained slim. They didn’t get diabetes. They didn’t get heart disease. They also lived 20 percent longer. And that’s just one example of 23,000 genes.

We’re involved with a company where we add a gene to people who are missing a gene that causes a terminal disease called pulmonary hypertension, and the treatment has actually worked in human trials. We can subtract genes. We can modify stem cells to have desirable effects such as rejuvenating the heart if it’s been damaged in a heart attack, which is true of half of all heart attack survivors.

We’ll soon have the ability to rejuvenate all the body’s tissues and organs and develop drugs targeted specifically at the underlying metabolic process of a disease rather than taking a hit-or-miss approach. But nanotechnology is where we really move beyond biology.

By the 2020s we’ll start using nanobots to complete the job of the immune system. Our immune system is great, but it evolved thousands of years ago when conditions were different. It was not in the interest of the human species for individuals to live very long, so people typically died in their 20s.

The life expectancy was 19. Your immune system, for example, does a poor job on cancer. It thinks cancer is you. It doesn’t treat cancer as an enemy. It also doesn’t work well on retroviruses. It doesn’t work well on things that tend to affect us later in life, because it didn’t select for longevity.

We can finish the job nature started with a nonbiological T cell. T cells are, in fact, nanobots—natural ones. They’re the size of a blood cell and are quite intelligent. I actually watched one of my T cells attack bacteria on a microscope slide. We could have one programmed to deal with all pathogens and could download new software from the internet if a new type of enemy such as a new biological virus emerged.

As they gain traction in the 2030s, nanobots in the bloodstream will destroy pathogens, remove debris, rid our bodies of clots, clogs and tumors, correct DNA errors and actually reverse the aging process. One researcher has already cured type 1 diabetes in rats with a blood-cell-size device.

Ray believes we will reach a point around 2029 when medical technologies will add one additional year every year to your life expectancy. By that he don’t mean life expectancy based on your birthdate but rather your remaining life expectancy.

Ray Kurzweil looks at progress and the future of nanotech, genetics and robotics over ten years after the Singularity is Near

Kurzweil identifies genetics, nanotechnology, and robotics as the three overlapping revolutions which will define our lives in the decades to come. In what ways are these technologies revolutionary?

  • The genetics revolution will allow us to reprogram our own biology.
  • The nanotechnology revolution will allow us to manipulate matter at the molecular and atomic scale.
  • The robotics [and AI] revolution will allow us to create a greater than human non-biological intelligence.
Major innovations in biotech over the last decade include:

  • Induced Pluripotent Stem Cells (iPSC)
  • Human Genome Editing (CRISPR)
  • 3D Bioprinting
  • $1,000 Genome
  • Lab Grown Tissues
  • DNA Storage
  • Rise of Citizen Biohackers
Kurzweil proposes that most diseases will be curable and the aging process will be slowed or perhaps even reversed in the coming decades.

Experimental Nanotechnology today includes:

  • Smart Contact Lenses
  • Tiny 3D Printed Batteries
  • Cancer-killing nanoparticles
  • DNA-based Computing

April 21, 2016

NASA and US Airforce projects to transform aviation with hypersonic and superefficient planes

NASA has several projects aimed at transforming aviation.

• Thrust 1 – Safe, Efficient Growth in Global Operations
- Transition from Terminal Area optimization to Gate-to Gate TBO
• Thrust 2 – Innovation in Commercial Supersonic Aircraft
- Initiate Low Boom Flight Demonstrator Project
• Thrust 3 – Ultra Efficient Commercial Vehicles
– Initiate planning for Flight Demonstration of N+2 / N+3 configurations and technologies
– Develop plans for research and ground demonstration of small core engine technologies
– Develop plans for research and technology development for flex fuel combustors that operate at higher alternative fuel fractions. In addition, planning should anticipate supporting the community with additional alternative fuel characterization tests
– Develop plans to fully implement CFD 2030
• Thrust 4 – Transition to Low Carbon Propulsion
– Develop baseline plans for hybrid-electric propulsion research and development, consistent with Thrust 4 roadmapping, including technical challenges that utilize research results from small-scale demos, such as SCEPTOR
• Thrust 5 - Real-Time System-Wide Safety Assurance
– Develop a comprehensive assessment of ARMD’s Verification and Validation (V and V) efforts
– Develop initial, focused TCs and funding requirements to implement the Thrust 5 roadmap
• Thrust 6 - Assured Autonomy for Aviation Transformation
– Develop a cohesive framework and strategy for achieving full integration of UAS into the NAS (AOSP and IASP)
– Develop initial, focused TCs and funding requirements (beyond current funded UAS TCs) to implement the Thrust 6 roadmap

– NASA will also establish the Hypersonics Technology Project. NASA will balance investments that support and leverage the work of the Department of Defense (DoD) with investments in fundamental hypersonics research.
– The project objective is to advance and utilize analytical tools, test techniques and capabilities, and critical technologies to ensure U.S. supremacy in hypersonics for future national needs.
– The project will work with the DoD to develop a National Hypersonic Strategy (requested by OMB and OSTP). NASA’s investment will be informed by and aligned to the National Strategy.

New stronger steel will affordably make cars lighter and more fuel efficient

NanoSteel®, a leader in nanostructured steel materials, today announced the delivery of its first advanced high strength steel (AHSS) to General Motors for initial testing. Designed to provide automakers with a new standard in material performance, the sheet steel is poised to accelerate vehicle lightweighting initiatives focused on affordably meeting rising global fuel-economy regulations. Production of the material, targeted to the $100 billion-plus automotive steel market, is the result of a multi-year joint development program between NanoSteel and AK Steel Corporation—an industry-leading innovator in steel product development.

NanoSteel’s commercially produced automotive sheet steel overcomes the historical tradeoff between strength and formability by delivering exceptional levels of both properties at the same time (approximately 1200 MPa tensile strength and 50 percent elongation). The high strength allows designers to create parts utilizing thinner-gauge material (less weight) while the high elongation allows manufacturers to produce the newly designed parts without expensive processing techniques, employee retraining or additional capital costs. The unique combination of properties also allows engineers the design freedom to create novel part shapes, which further reduces weight.

“Many advanced materials with outstanding properties end up abandoned because they are too hard to use or too expensive to make,” said NanoSteel CEO and president David Paratore. “NanoSteel’s advanced high strength steel is designed to be both easy to produce—using conventional alloying elements with standard slab casting equipment; and easy to use—enabling the stamping and forming of parts at room temperature without additional manufacturing infrastructure or investment, such as that required for ‘hot’ stamped parts.”

H/T to Green car congress

NanoSteel is poised to meet the automotive industry’s performance target with AHSS designs that deliver both high strength and high ductility in cold formable steel. These unique performance capabilities will allow the use of thinner steel gauges and more complex geometry parts to maintain stiffness in the pursuit of lighter vehicles with better fuel economy.

NanoSteel’s AHSS enables the auto industry to continue to utilize steel’s existing infrastructure, scale and efficiencies versus switching to other lightweighting materials which may have higher costs, longer cycle times and limited availability.

The first applications of NanoSteel's AHSS sheet designs will be to form structural parts in body-in-white (BIW) vehicle systems. The body-in-white (BIW) typically represents more than 20% of vehicle weight and stands to benefit more than any other automotive system from the weight reducing capabilities of NanoSteel’s new AHSS.

The Corporate Average Fuel Economy (CAFE) regulations in the United States require improved fuel efficiency in future automobiles and light trucks every year through 2025. The miles per gallon (MPG) standard is progressively increasing at a rate of 5% per year averaged across all automobile models and 3.5% per year for light trucks culminating in a vehicle average of 54.5 MPG by 2025.

A 30% reduction in vehicle body-in-white (BIW) mass would represent an overall vehicle weight reduction of nearly 7%. With the add-on effects of compounded secondary weight savings, this would result in a total reduction of 13.5%. Based on an industry rule of thumb that for every 10% reduction in vehicle weight, there is an expected 7% increase in fuel economy, the compounded weight savings would then generate a 9.5% improvement in fuel economy. That is equivalent to nearly 3 MPG on a 30 MPG vehicle.

Offtopic- Music Icon Prince found dead and early deaths of Rock stars and Wrestlers

Prince (57) died at his Paisley Park recording studio and home in Chanhassen, Minnesota, near Minneapolis, on April 21, 2016, after suffering flu-like symptoms for several weeks

Other big music related deaths in 2016.
Maurice White -founder of Earth Wind and Fire
Glenn Frey of the Eagles
David Bowie

Big entertainment deaths in 2016
Garry Shandling

Rock star do die younger than the general population

Pro wrestlers also die early

Former Pro Wrestler Chyna died at 45.

There was an analysis of the deathrate of Pro wrestlers

Emdrive may be explained by quantized momentum, New Emdrive experiments are showing thrust replication and superconducting Cannae drive demo set for May 2016

A radio frequency (RF) resonant cavity thruster is a proposed type of electromagnetic thruster. Unlike conventional electromagnetic thrusters, a resonant cavity thruster uses no reaction mass and emits no directional radiation. Their design principles are not supported by prevailing scientific theories, apparently violating the law of conservation of momentum; as a result they are controversial.

Aerospace engineer Roger Shawyer designed the EmDrive in 2001 and has persistently promoted the idea through his company, Satellite Propulsion Research. Chemical engineer Guido Fetta designed the Cannae Drive, based on similar principles.

If they are found to work as claimed, providing thrust without consuming a propellant would revolutionise many propulsion applications.

Imagine something like the impulse drive in Star Trek. The Star Trek impulse drive may have been described in technical manual as a nuclear fusion powered drive using something like regular rocketry, but the Star Trek technical manual wanted to assist suspension of disbelief. In the Star Trek Stories Impulse drive could provide acceleration up to any limit desired by the writers and have it offset by antigravity. Also, there was generally no limit on fuel resources being expended. Therefore, the impulse drive in Star Trek per how it was used in the movies and books was more akin to a reactionless drive which provides excellent propulsion so long as the system has power. Impulse drive and EMdrive both still have speed of light (relativistic) limitations.

You would not have antigravity but whatever power level you could achieve would have constant acceleration up to relativistic limits. Limitations would be based on the energy density and energy levels of your power source.

There is write up on reactionless drives at projectrho.com

Cannae drive is preparing for another demonstration of our superconducting thruster technology in May. Here is a picture of our assembled thruster and test apparatus. The thruster is under vacuum and ready for cryogenic operation.

New Superconducting Cannae device demo

Various teams around the world have begun to build their own versions of the EmDrive and put them through their paces. And to everyone’s surprise, they’ve begun to reproduce Shawyer’s results. The EmDrive, it seems, really does produce thrust. In total, six independent experiments have backed Shawyer’s original claims.

How to explain the seeming violation of conservation of momentum from EMdrive and Cannae drive ? Quantized Momentum

Mike McCulloch at Plymouth University explanation is based on a new theory of inertia that makes startling predictions about the way objects move under very small accelerations.

Inertia is the resistance of all massive objects to changes in motion or accelerations. In modern physics, inertia is treated as a fundamental property of massive objects subjected to an acceleration. Indeed, mass can be thought of as a measure of inertia. But why inertia exists at all has puzzled scientists for centuries.

McCulloch’s idea is that inertia arises from an effect predicted by general relativity called Unruh radiation. This is the notion that an accelerating object experiences black body radiation. In other words, the universe warms up when you accelerate.

According to McCulloch, inertia is simply the pressure the Unruh radiation exerts on an accelerating body.

That’s hard to test at the accelerations we normally observe on Earth. But things get interesting when the accelerations involved are smaller and the wavelength of Unruh radiation gets larger.

At very small accelerations, the wavelengths become so large they can no longer fit in the observable universe. When this happens, inertia can take only certain whole-wavelength values and so jumps from one value to the next. In other words, inertia must quantized at small accelerations.

McCulloch says there is observational evidence for this in the form of the famous fly by anomalies. These are the strange jumps in momentum observed in some spacecraft as they fly past Earth toward other planets.

Arxiv - Testing quantised inertia on the emdrive

April 20, 2016

Asia's aircraft carriers compared including a 3D look at China's Liaoning aircraft carrier

The Center for Strategic and International Studies (CSIS) launched "ChinaPower," an immersive micro-website that offers never-before-seen features exploring China’s lone aircraft carrier in 3D, visualizes key economic and demographic data, and measures key social factors among other indicators of Chinese power.

“China’s emergence as a global power has far reaching implications for countries around the world,” said Bonnie Glaser, CSIS Senior Adviser for Asia and Director of the CSIS China Power Project. “Despite the growing interest in China, the nature of China’s rise is often misunderstood. ChinaPower dissects and analyzes China’s growing role on the international stage.”

With the most up-to-date research, interactive graphics, expert analysis and data collection, ChinaPower is a regularly updated site that addresses critical questions surrounding China's rise.

ChinaPower is the result of a collaboration between the CSIS China Power Project, led by Bonnie Glaser, and the CSIS iDeas Lab—CSIS’s in-house multimedia and web production studio.

China’s first aircraft carrier, the Liaoning, into service with the People’s Liberation Army Navy (PLAN) attracted considerable attention. It was originally built as a “heavy aircraft-carrying cruiser” for the Soviet Navy, the ship was laid down as the Riga and renamed the Varyag in 1990. A Chinese travel agency purchased the unfinished hull in 1998, and three years later the ship was towed from the Ukraine to China, where it underwent extensive modernization of its hull, radar, and electronics systems. After years of refits, the Liaoning was commissioned into the PLAN in September 2012 as a training ship unassigned to any of the Navy’s three major fleets. Two months after the ship was commissioned, the PLAN conducted its first carrier-based takeoff and landings. Although the Chinese have made significant progress in developing their carrier program, it will be several years before a carrier air regiment is fully integrated into the PLAN.

The Liaoning is by no means a small ship, but it is far from the largest or most capable carrier in the Asia-Pacific. The Liaoning displaces roughly 60,000 tons — over 30,000 tons more than the Japanese helicopter destroyer Izumo — and is nearly 60 meters longer. The Liaoning also boasts a size advantage over the Soviet-built Indian carrier Vikramaditya, with a deck 20 meters longer and weighing approximately 15,000 tons more.

The Liaoning’s size falls well below the U.S. Nimitz-class carrier USS Ronald Reagan currently stationed with the U.S. Seventh Fleet in Japan, the latter being over 45 percent heavier and 30 meters longer. The Ronald Reagan weighs 97,000 tons fully loaded and spans 333 meters long, far outsizing the Liaoning. The numbers bear out the fact that the Liaoning is neither a lightweight nor a supercarrier like the USS Ronald Reagan.

UC Irvine invents nanowire battery material with off-the-charts charging capacity

University of California, Irvine researchers have invented nanowire-based battery material that can be recharged hundreds of thousands of times, moving us closer to a battery that would never require replacement. The breakthrough work could lead to commercial batteries with greatly lengthened lifespans for computers, smartphones, appliances, cars and spacecraft.

Scientists have long sought to use nanowires in batteries. Thousands of times thinner than a human hair, they’re highly conductive and feature a large surface area for the storage and transfer of electrons. However, these filaments are extremely fragile and don’t hold up well to repeated discharging and recharging, or cycling. In a typical lithium-ion battery, they expand and grow brittle, which leads to cracking.

UCI researchers have solved this problem by coating a gold nanowire in a manganese dioxide shell and encasing the assembly in an electrolyte made of a Plexiglas-like gel. The combination is reliable and resistant to failure.

The testing electrode was cycled up to 200,000 times over three months without detecting any loss of capacity or power and without fracturing any nanowires.

American Chemical Society ACS Energy Letters - 100k Cycles and Beyond: Extraordinary Cycle Stability for MnO2 Nanowires Imparted by a Gel Electrolyte

Stronger Ceramic Parts for Airplanes and industrial applications can now be 3D printed

A new way of making these tough materials could be a key step in producing better airplane engines and long-lasting machine parts. Ceramics are some of the hardest materials on Earth. They can withstand extreme temperatures, and some are impervious to friction, scratching, and other mechanical stresses that wear out metal and plastic. But it can be difficult to make complex shapes out of the materials.

Chemists at HRL Laboratories in Malibu, California, may have gotten around that problem by developing ceramics that can be made in a 3-D printer. The result: ultrastrong objects that are impossible to make using conventional methods.

Ceramics are used today in brake pads, the housing of microelectronics, and thermal shielding tiles (like the ones on spacecraft). Now the scientists at HRL are trying to substantially expand the applications. If parts for aircraft engines were made of ceramic, for example, the engines could run at a higher temperature, increasing their efficiency.
Ceramics could also offer an upgrade on parts used in steam turbines and other machines that must withstand searing, mechanically harsh conditions.

HRL’s trick is to formulate special resins that can be used as the ink in a printer. They are made out of polymers but carry in their molecular structure silicon and other elements found in ceramics. These resins are loaded into 3-D printers to make parts with baroque shapes, such as corkscrews and sheets of intricate lattices. Then those parts go into a furnace to bake out the organic polymer components, leaving behind ceramic material.

The 3-D-printed ceramics could be better in some respects than their conventional counterparts. One lattice made at HRL has 10 times the compressive strength of commercially available ceramics. These printed parts can also tolerate heats as high as 1,700 °C, a temperature at which other ceramics start to degrade.
But the group still hopes to make its printed ceramics stronger. One approach is to design new kinds of pre-ceramic polymers that have fibers embedded in them to stop cracks from spreading.

Left: In addition to printing individual parts, the process can yield lattices like this one, which can be flexed and twisted to make more complex shapes or to fit a surface such as an airplane wing.

Metal-foam hybrid has potential in soft robotics, aeronautics

Imagine an aircraft that could alter its wing shape in midflight and, like a pelican, dive into the water before morphing into a submarine.

Impossible, you say? A little too “Transformers,” perhaps? Well, the U.S. Air Force doesn’t think so, and believes Cornell engineering professor Rob Shepherd and his group might help make that futuristic-sounding vehicle a reality.

The key is a hybrid material featuring stiff metal and soft, porous rubber foam that combines the best properties of both – stiffness when it’s called for, and elasticity when a change of shape is required. The material also has the ability to self-heal following damage.

If you’re thinking T-1000, the shape-shifting android assassin from “Terminator 2,” it’s not quite like that. But you’re not far off.

The metal/foam compound developed in the lab of associate professor of engineering Rob Shepherd can be heated in order to change its shape, then cooled to regain stiffness. It has potential applications in soft robotics and aeronautics.

Advanced Materials - Morphing Metal and Elastomer Bicontinuous Foams for Reversible Stiffness, Shape Memory, and Self-Healing Soft Machines

India will buy 36 French Rafale Fighter Jets for nearly $9 billion

India has agreed to pay $8.8 billion to France's Dassault for 36 fighter jets as sources from both countries hinted a long-delayed deal to purchase the aircraft was imminent. The final agreement is set to be signed in India in three weeks, but delivery of the aircraft will not take place for another 18 months.

The Dassault Rafale fighter jet is almost completely French, with fuselage, avionics, engines and weapons all made in that country. Rafales have flown in combat in Afghanistan, Libya, Mail and Iraq. France operates 140 Rafales including the Rafale M, a navy version of the fighter featuring strengthened landing gear and a tail hook for use on aircraft carriers.

Although relatively small compared to planes like the Eurofighter Typhoon and F-22 Raptor, Rafale packs a powerful punch. Twelve wing-mounted hard points can carry a combination of air-to-air missiles, air-to-ground missiles, sensors, and drop tanks. Despite the fact that the Rafale is now a 30-year-old design, upgrades such as the RBE2 AA active electronic scanning array (AESA) radar, Damocles targeting pod, Meteor air-to-air missiles, and SCALP cruise missiles have kept the design competitive with other so-called "4+ generation" fighters.

In January 2014, Defence Minister Jean-Yves Le Drian announced that €1 billion is allocated towards the development of the F3R standard. The standard will see the integration of the Meteor BVR missile, among other weapons and software updates. The standard is to be validated by 2018. The Rafale is planned to be the French Air Force's primary combat aircraft until 2040 or later.

April 19, 2016

Update on laser enrichment of uranium

Australian company Silex Systems is considering taking an equity position in Global Laser Enrichment (GLE), the exclusive licensee for its laser uranium enrichment technology, after GE-Hitachi Nuclear Energy announced its intention to exit the company.

GLE is a joint venture between GE (51%), Hitachi (25%) and Cameco (24%) and has exclusive rights to commercially develop the SILEX laser isotope separation process technology developed by Silex Systems under an agreement signed in 2006.

In 2012, the company received a construction and operation licence for a full-scale laser enrichment facility - the first ever granted anywhere for such a plant - from the US Nuclear Regulatory Commission (NRC). The first phase of a three-phase program to commercialize the technology - a test loop demonstration - was successfully completed at GLE's facility in Wilmington, North Carolina, in 2012. The second phase of the program, including economic and engineering validation for the initial commercial production module, began the same year.

GLE was selected by the US Department of Energy (DOE) to enter contract negotiations on the construction of a laser enrichment plant at the DOE's former gaseous enrichment site at Paducah, Kentucky to re-enrich its inventory of high-assay depleted uranium tails. Although those negotiations are continuing, the pace of commercialization activities was slowed in 2014 when GLE underwent restructuring.

Silex Systems CEO Michael Goldsworthy said that the relationship had been a productive one and that his company respected GE-Hitachi's decision to exit GLE, which was precipitated by a change in business priorities at GE-Hitachi Nuclear Energy. "Whilst this is disappointing, we are encouraged by interest from within the nuclear industry and opportunities that may eventuate once the nuclear fuel markets recover from the current downturn," he said. "We believe this is a game-changing technology which can enter the market and make a difference to nuclear fuel economics as nuclear power inevitably comes back into favour in an emissions constrained world," he added.

In response to GE-Hitachi's decision, Silex Systems is considering increasing its direct participation in the development project and is negotiating a term sheet with GE-Hitachi that would effectively give Silex the option to take an equity position in GLE, the company said in a statement.

Silex also said that it is "reviewing the possibility" of contributing up to AUD 10 million ($7.8 million) of funding for ongoing activities at its laser facility at Lucas Heights, Sydney and at GLE's Wilmington facility to ensure that the current budget for 2016 continues to be adequately funded while discussions are held with potential investors.

Laser enrichment uses a laser beam to preferentially excite the uranium-235 isotope in gaseous uranium hexafluoride, which can then be separated. Its proponents claim that it has the potential to be more efficient than the centrifuge enrichment technology that is currently used to produce enriched uranium on a commercial scale. The principles of the SILEX (Separation of Isotopes by Laser EXcitation) process were formulated by Goldsworthy and Horst Struve in the early 1990s, but the technology is classified under US and Australian law.

Silex Systems noted that Cameco, who acquired a 24% share in GLE in 2008, "remains supportive of the Silex efforts".

April 18, 2016

3d printing of rocket parts and liquified natural gas fuel could also dramatically lower launch costs

Reusable rockets could greatly lower rocket launch costs but two other significant emerging technologies are 3D printing and liquified natural gas rocket fuel.

Liquefied natural gas, which is a commercially available form of methane, could have several advantages as a rocket fuel. Blue Origin has said its wide availability and low cost would enable an "extended engine development test program." Methane is also clean, meaning it's less likely to clog fuel lines inside the engine. That would reduce the type of rigorous cleaning needed to clear those particulates and make it easier for reusability, said Ann Karagozian, UCLA professor of mechanical and aerospace engineering. The gas also self-pressurizes, which could eliminate the need for tank-pressurization systems.

The combination could enable a simple, reliable design that is easy to manufacture. It could be a game changer.

SpaceX is also developing a liquid-oxygen-and-methane staged combustion engine called Raptor.

3-D printing: Additive manufacturing, commonly known as 3-D printing, can substantially reduce the time and cost of producing rocket parts.

Take the main oxidizer valve body in one of the SpaceX Falcon 9 rocket engines, for example. The part, which controls the flow of oxygen into the engine, was produced through 3-D printing in less than two days and launched on a Falcon 9 in 2014. That marked the first time that SpaceX flew a 3-D printed part. Normally, that process would have taken months, the company said in a blog post at the time.

SpaceX said that compared with a traditionally cast part, the printed valve body had "superior strength, ductility and fracture resistance." After undergoing a rigorous test program, the 3-D printed part was qualified to fly interchangeably with cast parts on all Falcon 9 missions, the company said.

Additive manufacturing has been used for individual parts and components up to SpaceX's SuperDraco engine chamber for the Dragon Version 2 spacecraft and Aerojet's demonstration rocket engine. The SuperDraco engine chamber was printed in Inconel, a superalloy. The engines will power a launch escape system.

3D printing could make many specialized and expensive parts cheaper and lower weight.

China Bohai undersea tunnel will be over twice as long as Chunnel and should break ground this year

The Bohai Strait Tunnel or Dalian-Yantai Tunnel project proposes the construction of an underwater tunnel to connect Dalian on the Liaodong Peninsula to Yantai on the Shandong Peninsula. Another name for the project is Cross-Bohai-Strait channel.

Crossing the Bohai Strait the tunnel would be 123 kilometers (76 mi) long, 90 kilometers (56 mi) of it under water. This would exceed the combined lengths of the two longest undersea tunnels on Earth, the Seikan Tunnel and the Channel tunnel.

The planned high speed railway would traverse Bohai Bay, connecting Dalian in the south of Liaoning province with the Shandong province city of Yantai. "It will reduce travel time across Bohai Bay to a mere 40 minutes," Wang commented.

At present, a ferry ride across the bay takes about eight hours, while travelling between the two cities by vehicle means covering 1,400 kilometers of coastal roads.

A tunnel between Hong Kong-Macau-Guangzhou-Shenzhen and Zhuhai was considered but Hong Kong Macau bridge is being built instead.

This tunnel will be building experience for even longer tunnels.

The Taiwan Strait Tunnel Project is a proposed undersea tunnel to connect Pingtan in China to Hsinchu in Taiwan as part of the G3 Beijing–Taipei Expressway It would be 150 kilometers long.

A tunnel could link Incheon, South Korea and Weihai of Shandong Province. They are about 340 kilometers apart.

A Bering Strait tunnel would not be as long relative to the other big tunnel projects. A Bering Strait tunnel would be about 103-kilometers (64 mi) long. The Bering strait is no deeper than 55 meters.

With the two Diomede Islands between the peninsulas, the Bering Strait could be spanned by three bridges. Two long bridges, each almost 40 kilometers (25 mi) long, would connect the mainland on each side to one island, and a third much shorter one between the two islands.

DARPA Vertical Take-Off/Landing X-plane Program Achieves Critical Milestone

The DARPA Vertical Take-Off/Landing X-plane (VTOL x-plane) Program achieved a critical milestone as Aurora Flight Sciences' subscale vehicle demonstrator successfully flew at a U.S. military facility. The flight of the subscale aircraft met an important DARPA risk reduction requirement, focusing on validation of the aerodynamic design and flight control system

“The successful subscale aircraft flight was an important and exciting step for Aurora and our customer,” said Tom Clancy, Aurora’s chief technology officer. “Our design’s distributed electric propulsion system involves breaking new ground with a flight control system requiring a complex set of control effectors. This first flight is an important, initial confirmation that both the flight controls and aerodynamic design are aligning with our design predictions.”

The subscale aircraft weighs 325 pounds and is a 20% scale flight model of the full scale demonstrator Aurora will build for DARPA in the next 24 months. The wing and canard of the subscale vehicle utilize a hybrid structure of carbon fiber and 3D printed FDM plastics to achieve highly complex structural and aerodynamic surfaces with minimal weight. The unmanned aircraft take-off, hover and landing was controlled by Aurora personnel located in a nearby ground control station with oversight and coordination by U.S. government officials including DARPA personnel.

On March 3, 2016, DARPA announced the award of the Phase II contract for the VTOL X-Plane contract to Aurora, following a multi-year, Phase I design competition. The program seeks to develop a vertical take-off and landing demonstrator aircraft that will achieve a top sustained flight speed of 300 kt – 400 kt, with 60-75% increase in hover efficiency over existing VTOL aircraft. Aurora’s design is for the first aircraft in aviation history to demonstrate distributed hybrid-electric propulsion using an innovative synchronous electric-drive system. Having successfully completed the subscale demonstrator flight, Aurora’s LightningStrike team will focus over the next year on further validation of flight control system and configuration of the full scale VTOL X-Plane demonstrator.

Novel miniaturized circulator opens way to doubling wireless capacity

Researchers developed a microelectronic substitute for larger-scale magnetic components and open a pathway to more efficient communications and more capable radar systems

A DARPA-funded team has drastically miniaturized highly specialized electronic components called circulators and for the first time integrated them into standard silicon-based circuitry. The feat could lead to a doubling of radiofrequency (RF) capacity for wireless communications—meaning even faster web-searching and downloads, for example—as well as the development of smaller, less expensive and more readily upgraded antenna arrays for radar, signals intelligence, and other applications.

The defining feature of circulators is that RF signals, in the form of electronic waves in the circuitry, travel only in a forward direction with reverse propagation of the wave forbidden by the physics of the circuit. That’s what you need for minimizing on-chip interference and for keeping signals separated. Most materials can’t play this role because RF traffic can flow both ways through them; these materials exhibit what engineers refer to as reciprocal behavior. Nonreciprocal components like the new circulator, on the other hand, act like one-way highways for RF signals. Traditionally, circulators have relied on external, ferrite-based magnets to force RF signals into a one-way course through downstream circuitry. Those magnets and ferrite materials have rendered the circulators bulky, expensive, and incompatible with the workhorse microcircuit technology, known by insiders as CMOS, which stands for complementary metal-oxide semiconductor. So it has been hard to miniaturize circulators for CMOS integrated circuits.

The Columbia researchers got around this roadblock to miniaturization by coming up with a path-breaking design that does away with the need for bulky ferrites and magnets. Their design achieves the one-way RF flow with a series of capacitors coordinated with a minuscule and precise clock, electronically emulating the direction-dictating magnetic “twist” that in conventional ferrite circulators is imposed on RF signals by an external magnetic field. That novel design makes possible an unprecedented microelectronic assemblage: A receiver connected to one “on-ramp” (or port) of the new circulator structure; a transmitter connected to another port of that same circulator; and an antenna shared by those two tiny devices, itself coupled to the circulator via a third port situated between the other two. Since the RF propagation is one way (non-reciprocal) in the circulator, the transmitted and received signals smoothly traverse their respective paths without getting mixed up with one another.

That clean segregation of received and transmitted signals opens a powerful new capability. In most two-way RF systems, transmission and reception at a given frequency have to be staggered in time with a switching process, slowing communication speeds. The way around this bottleneck has been to transmit and receive at two different frequencies, which requires twice as much spectrum—a limited resource. By contrast, the new pinky-nail-sized circulator opens the door to communications and radar systems operating in full duplex mode—that is, transmitting and receiving at the same frequency at the same time with a single shared antenna.

“This new circulator component could enable full-duplex systems that let you speak and listen all at once,” said William Chappell, director of DARPA’s Microsystems Technology Office. In radar applications, this capability could put an end to brief but potentially deadly blind moments since the system would not have to toggle between separate transmission and reception modes. And by halving the frequency needs, Krishnaswamy said, “full-duplex communication has the potential to double a network’s capacity” for voice, data, and other forms of information. In powerful radar and other RF systems that require large arrays of transmitters and receivers, he continued, “a compact, efficient, high-performance circulator” makes it easier for RF engineers to make their systems smaller. Finally, noted Chappell, the new circulator’s CMOS-compatibility feature is critical because it should ease integration into existing chip-manufacturing methods, potentially making all the difference between a laboratory achievement that stays in the lab and one that transforms a raft of RF technologies.

The work is under the Arrays at Commercial Timescales (ACT) project.

Today’s electromagnetic (EM) systems use antenna arrays to provide unique capabilities, such as multiple beam forming and electronic steering, which are important for a wide variety of applications such as communications, signal intelligence (SIGINT), radar, and electronic warfare. However, wider use of arrays has been limited by lengthy system development times and the inability to upgrade already- fielded capabilities—problems exacerbated by the fact that military electronics have evolved at a slower cadence than in the commercial sector. In particular, the performance gap is widening between the radio frequency (RF) capabilities of fielded military systems and the continuously improving digital electronics surrounding those systems. The Arrays at Commercial Timescales (ACT) aims to shorten design cycles and in-field updates and push past the traditional barriers that lead to 10-year array development cycles, 20- to 30-year static life cycles and costly service-life extension programs.

Specifically, as an alternative to large undertakings focused on traditional monolithic array systems, ACT seeks to develop a digitally-interconnected building block from which larger systems can be formed. The desired building block, composed of a common module and a reconfigurable EM interface, would be scalable and customizable for each application, without requiring a full redesign for each application space.

The ACT program has two thrusts, each focused on a specific enabling technology for rapidly upgradable and widely deployable array architectures:

  • A digitally-influenced common module comprising 80 to 90 percent of an array’s core functionality for insertion into a wide range of applications

  • Reconfigurable and tunable RF apertures for spanning S-band to X-band frequencies (and points between) for a wide variety of characteristics

Nature Communications - Magnetic-free non-reciprocity based on staggered commutation

Many accurate enough chips will use software for correction to achieve up to 10,000 times higher speed and lower power usage

Interested in solving tasks that benefit from floating point (“fp”),
but IEEE floating point unit takes over 500,000 transistors

• Could less accurate fp arith unit (eg, 1% error) be very small?
• Yes: at least 100x smaller - O(5000) transistors - will sketch
• If errors can be compensated in application software, can get 10,000x better speed, power than CPU (100x GPU)

DARPA funded the creation of Joseph Bates Singular Computing LLC’s chip because fuzziness can be an asset when it comes to some of the hardest problems for computers, such as making sense of video or other messy real-world data. “Just because the hardware is sucky doesn’t mean the software’s result has to be,” says Bates.

Bates has worked with Sandia National Lab, Carnegie Mellon University, the Office of Naval Research, and MIT on tests that used simulations to show how the S1 chip’s inexact operations might make certain tricky computing tasks more efficient. Problems with data that comes with built-in noise from the real world, or where some approximation is needed, are the best fits. Bates reports promising results for applications such as high-resolution radar imaging, extracting 3-D information from stereo photos, and deep learning, a technique that has delivered a recent burst of progress in artificial intelligence.

In a simulated test using software that tracks objects such as cars in video, Singular’s approach was capable of processing frames almost 100 times faster than a conventional processor restricted to doing correct math—while using less than 2 percent as much power.

Bates is not the first to pursue the idea of using hand-wavy hardware to crunch data more efficiently, a notion known as approximate computing as others have tried Probabilistic Chips. But DARPA’s investment in his chip could give the fuzzy math dream its biggest tryout yet.

Bates is building a batch of error-prone computers that each combine 16 of his chips with a single conventional processor. DARPA will get five such machines sometime this summer and plans to put them online for government and academic researchers to play with. The hope is that they can prove the technology’s potential and lure interest from the chip industry.

DARPA has the Unconventional Processing of Signals for Intelligent Data Exploitation (UPSIDE) project for this work.

Ultrathin organic material enhances e-skin display

University of Tokyo researchers have developed an ultrathin, ultraflexible, protective layer and demonstrated its use by creating an air-stable, organic light-emitting diode (OLED) display. This technology will enable creation of electronic skin (e-skin) displays of blood oxygen level, e-skin heart rate sensors for athletes and many other applications.

Integrating electronic devices with the human body to enhance or restore body function for biomedical applications is the goal of researchers around the world. In particular, wearable electronics need to be thin and flexible to minimize impact where they attach to the body. However, most devices developed so far have required millimeter-scale thickness glass or plastic substrates with limited flexibility, while micrometer-scale thin flexible organic devices have not been stable enough to survive in air.

The research group of Professor Takao Someya and Dr. Tomoyuki Yokota at the University of Tokyo's Graduate School of Engineering has developed a high-quality protective film less than two micrometers thick that enables the production of ultrathin, ultraflexible, high performance wearable electronic displays and other devices. The group developed the protective film by alternating layers of inorganic (Silicon Oxynitrite) and organic (Parylene) material. The protective film prevented passage of oxygen and water vapor in the air, extending device lifetimes from the few hours seen in prior research to several days. In addition, the research group were able to attach transparent indium tin oxide (ITO) electrodes to an ultrathin substrate without damaging it, making the e-skin display possible.

Smart e-skin system comprising health-monitoring sensors, displays, and ultraflexible PLEDs. (A) Schematic illustration of the optoelectronic skins (oe-skins) system. (B) Photograph of a finger with the ultraflexible organic optical sensor attached. (C) Photographs of a human face with a blue logo of the University of Tokyo and a two-color logo. The brightness can be changed by the operation voltage. (D) Photograph of a red seven-segment PLEDs displayed on a hand.

Science Advances - Ultraflexible organic photonic skin

Petahertz optical drive with wide-bandgap semiconductor

High-speed photonic and electronic devices at present rely on radiofrequency electric fields to control the physical properties of a semiconductor, which limits their operating speed to terahertz frequencies (10^12 Hz). Using the electric field from intense light pulses, however, could extend the operating frequency into the petahertz regime (10^15 Hz). Here we demonstrate optical driving at a petahertz frequency in the wide-bandgap semiconductor gallium nitride. Few-cycle near-infrared pulses are shown to induce electric interband polarization though a multiphoton process. Dipole oscillations with a periodicity of 860 as are revealed in the gallium nitride electron and hole system by using the quantum interference between the two transitions from the valence and conduction band states, which are probed by an extremely short isolated attosecond pulse with a coherent broadband spectrum. In principle, this shows that the conductivity of the semiconductor can be manipulated on attosecond timescales, which corresponds to instantaneous light-induced switching from insulator to conductor. The resultant dipole frequency reaches 1.16 PHz, showing the potential for future high-speed signal processing technologies based on wide-bandgap semiconductors.

Temporal characterization of IAP based on attosecond streak

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