Progress to Ultralight 16 Square Meter Nanocrystal Solar Sails for Breakthrough Starshot

Breakthrough Starship wants to use a 100 Gigawatt laser array to push an ultralight 4 meter X 4 meter nanocrystal solar sail.

StarChip is the name used by Breakthrough Initiatives for a very small, centimeter-sized, gram-scale, interstellar spacecraft envisioned for the Breakthrough Starshot program. The light sail is envisioned to be no larger than 4 by 4 meters (13 by 13 feet). The material would have to be very thin and be able to reflect the laser beam while absorbing only a small fraction of the incident energy, or it will vaporize the sail. The light sail may also double as power source during cruise, because collisions with atoms of interstellar medium would deliver 60 watt/m2 of power. They want to keep the light sail and the Starschip under 1 gram of mass. A penny weighs 2.5 grams.

A 2018 paper described the material challenges of the Starchip and its Solar sail.

Lubin’s preliminary calculations indicate that a 100-GW phased laser array 10 km on a side could accelerate each Starchip spacecraft to 0.2c (20 percent of the speed of light) by firing for roughly three minutes.

A group that already made nanocrystal films 16000 times larger is adding origami construction into the films to add more components and structure without making the system heavier. They are making the photonic chips 50 nanometers thick.