The hybrid magnetic tunnel junction fabricated to achieve electrical detection of spin polarization of the organic-based magnetic semiconductor
Researchers at Ohio State University have demonstrated the first plastic (spintronic) computer memory device that utilizes the spin of electrons to read and write data.
Epstein described the material as a hybrid of a semiconductor that is made from organic materials and a special magnetic polymer semiconductor. As such, it is a bridge between today’s computers and the all-polymer, spintronic computers that he and his partners hope to enable in the future.
Spintronics would effectively let computers store and transfer twice as much data per electron. But higher data density is only part of the story. “Spintronics is often just seen as a way to get more information out of an electron, but really it’s about moving to the next generation of electronics,” Epstein said. “We could solve many of the problems facing computers today by using spintronics.”
* Flipping the spin of an electron requires less energy (more energy efficieny
* produces very little heat
* Spintronic devices could run on smaller batteries.
* If they were made out of plastic, they would also be light and flexible.
The new paradigm of electronics, ‘spintronics’, promises to extend the functionality of information storage and processing in conventional electronics1. The principal spintronics device, the ‘spin valve’, consists of two magnetic layers decoupled by a spin-transporting spacer, which allows parallel (on) and antiparallel (off) alignment of the magnetizations (spins) of the two magnetic layers. The device resistance then depends on the spin alignment controlled by the external magnetic field. In pursuit of semiconductor spintronics, there have been intensive efforts devoted to develop room-temperature magnetic semiconductors and also to incorporate both inorganic semiconductors and carbon-based materials as the spin-transporting channels. Molecule/organic-based magnets, which allow chemical tuning of electronic and magnetic properties, are a promising new class of magnetic materials for future spintronic applications. Here, we report the realization of an organic-based magnet as an electron spin polarizer in the standard spintronics device geometry. A thin non-magnetic organic semiconductor layer and an epitaxial ferromagnetic oxide film were employed to form a hybrid magnetic tunnel junction. The results demonstrate the spin-polarizing nature of the organic-based magnetic semiconductor, vanadium(TCNE: tetracyanoethylene)x (x ∼ 2; Tc ∼ 400 K), and its function as a spin injector/detector in hybrid magnetic multilayer devices.