Researchers develop an all-electric method to measure the spin texture of topological insulators

Researchers from Singapore's NUS and the University of Missouri developed a new all-electric method to measure the spin texture of topological insulators. The researchers say that this method could lead to an easier (and cheaper) methods of developing spintronics devices.

Spin Texture measurements of Topological Insulators (NUS)

The new work revealed a close relation between the spin texture of topological surface states (TSS) and a new kind of magneto-resistance. The researchers observed the second order nonlinear magneto-resistance in a prototypical 3D TI Bi2Se3 films, and showed that it is sensitive to TSS. In contrast with conventional magneto-resistances, this new magneto-resistance shows a linear dependence on both the applied electric and magnetic fields.

Zero-Field Switching effect discovered in cobalt-iron-boron

Researchers from Johns Hopkins University and the US NIST discovered that magnetisation in a cobalt-iron-boron layer could be flipped between stable states using only electric current, without an external magnetic field. The researchers call this effect Zero-Field Switching (ZFS).

ZFE in cobalt-iron-boron layer (JHU / NIST)

The researchers say that this effect was not theoretically predicted, as all previous devices of this type have required a magnetic field or other more complex measures to change the material's magnetisation.

Researchers develop a Magnon Spin Valve

Researchers from Johannes Gutenberg University Mainz (JGU), the University of Konstanz and Tohoku University developed a spin-valve structure based on several ferromagnets - which can detect the efficiency of magnon currents depending on the magnetic configuration of the device.

Magnon Spin valve (Tohoku JGU)

The researchers say that this is a new "building block" for Magnon Spintronics, and this kind of device could be used to the transmission or blocking of incoming spin information.

Spin Caloritronics explored for DNA molecules

Spin caloritronics is a new emerging field that explores how heat currents transport electron spin. One interesting application in this field is the use of waste heat to create spintronics devices that do not require any external power to operate.

dsDNA sandwiched between a nonmagnetic metal (NM) and a ferromagnet (FM) one (photo: CUMT)

The thermally driven transport application of spin caloritronics is based on the Seebeck effect - which takes use of the temperature difference between a ferromagnet (FM) and a nonmagnetic metal (NM) to create a thermoelectric voltage.

Researchers from MIPT design a new spin diode

Researchers from the Moscow Institute of Physics and Technology (MIPT) designed a new spin diode, using two kinds of antiferromagnetic materials. The researchers say that this new design features triple the frequencies range under which the device can rectify alternating currents, while keeping the same sensitivity as semiconductor-based diodes.

Spin Diode Design (MIPT)

The spin diode, in this new design, is placed between the two materials, and by adjusting the orientation of their antiferromagnetic axes, it is possible to change the resistance and the resonant frequency of the diode.

Researchers develop a magnons-based spin transistor

Researchers from the University of Groningen developed a spin transistor based on magnons (spin-waves). This transistor allows the researchers to alter the flow of spin waves through a magnet - with only an electrical current.

Magnon transistor schematics (Groningen University)

To create the transistor, the researchers used films of platinum that inject magnons into a magnet made of Yttrium Iron Garnet (YIG). A third platinum strip, inserted between the injector and detector allows the researchers to either inject additional magnons in the conduction channel or drain magnons from it.

Researchers modify graphene to make the material both magnetic and with spin-orbit interaction

Researchers from Russia, Germany and Spain managed to modify graphene to make the material both magnetic and with spin-orbit interaction, for the first time. This could make graphene suitable for quantum computers.

Graphene with the properties of cobalt and gold image

To achieve these new properties, the researchers combined graphene with gold and cobalt. The spin-orbit interaction, unlike in gold, is extremely small in graphene. The interaction between graphene and gold increases the spin-orbit interaction in graphene, while interaction between graphene and cobalt induced magnetism.

A new alloy break the magnetization density record

Researchers from Montana State University and Lawrence Berkeley National Laboratory developed a new thin film from iron, cobalt and manganese that boasts an average atomic moment potentially 50 percent greater than the Slater-Pauling limit -a magnetization density of 3.25 Bohr magnetons per atom.

The Slater-Pauling curve describes magnetization density for alloys. Up until today, the material tthat posted the maximum average atomic moment was an iron-cobalt (FeCo) binary alloy - with a maximum average atomic moment of 2.45 Bohr magnetons per atom.

Treated diamond plates show promise for spintronic devices

Researchers from Australia's La Trobe University find that when diamonds are treated in hydrogen plasma they incorporate the hydrogen atoms into the surface, and when exposed to moist air, they become electrically conductive. The researchers measured how strongly a charge carrier's spin interacts with a magnetic field in this diamond-based material and found the material to be promising for spintronic devices.

Diamond plates undergoing hydrogen plasma surface termination treatment

The diamond material features strong spin-orbit coupling, which enables one to control the particle's spin with an electric field. Following previous researchers, it is now found that these material features several interesting properties that could enable manipulation of spins in the conductive surface layer of diamond by either electric or magnetic fields.