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Spin-LED enable almost purely circularly polarized emission

Feb 10, 2017

Researchers from the Tokyo Institute of Technology managed to achieve an almost purely circularly polarized (CP) electroluminescence (EL) in spin-polarized LEDs at room temperature without an external magnetic field.

Spin-LED design and images (Tokyo Institute of Technology)

The researchers used LEDs and a polycrystalline Fe in-plane spin injector. During the experiment the researchers injected spins of a given type, which were dispersed due to spin relaxation. Radiative recombination subsequently occurred, which was observed in the form of a linearly polarized emission. Almost pure circularly polarized emission was achieved when the current density was high enough.

MIT and JGU researchers advance towards skyrmion-based spintronics

Dec 30, 2016

Researchers from MIT and the Johannes Gutenberg University Mainz (JGU) achieved the billion-fold reproducible motion of skyrmions (special spin structures) between different positions. The researchers say that this kind of process is needed to produce magnetic shift registers - and so this is a critical step towards skyrmions applications in spintronics devices.

The magnetic structure of the skyrmion (image)

Using specially design thin film structures (asymmetric multilayer devices) that exhibit broken inversion symmetry that stabilize the skyrmions. In such structures, skyrmions have a unique stability - which makes them compelling for such spintronic devices. The researchers say that those skyrmions, that can be shifted by electrical currents and move relatively undisturbed through the track, are very promising to make racetrack devices.

NRL researchers produce spin-filtering at room temperature

Dec 22, 2016

Researchers from the US Naval Research Laboratory (NRL) demonstrated metallic spin filtering at room temperatures, using a ferromagnet-graphene-ferromagnet thin film junction device.

Spin filtering graphene junction (NRL)

Spin filtering has been theoretically predicted, and previously seen only for high-resistance structures at cryogenic temperatures. This is the first time that someone demonstrated the effect in room temperatures, and with very low resistance in arrays of multiple devices.

Researchers demonstrate the world's first spintronics-based AI

Dec 21, 2016

Researchers at Tohoku University demonstrated a spintronics-based artificial intelligence (AI) device. The researchers developed an artificial neural network using micro-scale magnetic spintronic device.

AI spintronics device photos (Tohoku Uni)

The researchers say that this spintronic device is capable of memorizing arbitral values between 0 and 1 in an analogue manner unlike the conventional magnetic devices, and thus perform the learning function, which is served by synapses in the brain. This is still an early stage (the researchers call this a proof-of-concept demo) but spintronics has a high potential to enable ultra low-power and fast neural-network devices.

Researchers demonstrate that thin-film Fe3O4 is a promising candidate for flexible spintronics

Nov 22, 2016

Researchers from National Chiao Tung University (NCTU) demonstrated that it is feasible to grow an epitaxial Fe3O4 film on a flexible muscovite. The thin film was characterized by several methods and found preserve the electrical and magnetic properties of Fe3O4. The researchers performed bending tests to confirm that the heterostructures retain the physical properties under repeated cycles. 

The researchers conclude their paper, saying that the material is a promising candidate for flexible spintronics devices, based on the tunneling magnetoresistance on the flexible muscovite.

A lateral electric field can control the spin polarization in zigzag graphene ribbons

Nov 16, 2016

Researchers from Grennole Alpes University in France have demonstrated using atomistic calculations that a lateral electric field can be used to tune the carrier mobility and change the spin polarization of the current driving through zigzag graphene ribbons. The researchers say that these effects can be nicely exploited in spintronics devices.

Spin polarization in ZGNR image

The calculations predict a high variation of the carrier mobility, mean free path and spin polarization in the ZGNRs. It turns out that configurations with almost 100% spin-polarized current can be switched on and off.