The interplay between current-driven spinвЂ“orbit torques and chiral magnetic texture at transition metal interfaces has resulted in very fast current-driven magnetization reversal, ultrafast domain wall propagation, and current-driven skyrmion motion. Д«ecause of the coexistence of strong spinвЂ“orbit coupling and magnetism, transition metals have occupied a prominent position in the development of spin-orbitronics. This broad area of research is called spin-orbitronics.

But when inversion symmetry is broken, such as in certain classes of magnetic crystals or at interfaces, spinвЂ“orbit coupling triggers a number of fascinating phenomena such as antisymmetric magnetic exchange giving rise to topologically nontrivial magnetic textures, spinвЂ“momentum locking, spinвЂ“orbit torques, chiral magnetic damping, etc. As a matter of fact, all the effects mentioned above exist in systems where inversion symmetry is preserved. Quite surprisingly, in spite of its already long history, this fundamental interaction has been pivotal to several revolutions in the past 10 years. It is central to magnetism and spintronics, where it drives magnetic anisotropy, spin relaxation, magnetic damping, anisotropic magnetoresistance, and anomalous Hall effect. SpinвЂ“orbit coupling lies at the core of condensed matter. Note that SOC systems are time-reversal symmetric, and so there will be no net spin polarization if the measurement is averaged over the entire Fermi surface.ДЄurГ©lien Manchon, Abderrezak Belabbes, in Solid State Physics, 2017 1 Introduction Both of these will result in wavevector (mode) selection, where only a portion of the Fermi surface is probed for spin detection. Mode-averaging can be partially overcome by designing devices that are spatially constrained in the transverse direction, or via an electron wave-guiding action effected by regions with different doping densities. Spin relaxation length is rather long in a ballistic semiconductor, but impurity scattering can weaken spin current considerably. Temperature smears the electron distribution over the double-conic Rashba bandstructure at the Fermi energy, greatly reducing ideal spin polarization. Spin orbit coupling based spintronics is still fraught with difficulty due to the poor вЂsurvivalвЂ™ of measurable spin current amidst such effects as temperature, impurity scattering, mode averaging, non-uniformity of spin orbit strength, as well as interfacial spin flips. The prospect of semiconductor spintronics thus remains unclear for the foreseeable future. This, in turn, is translated into a conductance modulation by incorporating a ferromagnetic drain electrode to the contact to act as the detector for the electron spin.ДЄlthough experiments 32 have confirmed the working principles of such devices, most have fallen short of demonstrating large conductance modulation. Electrical voltage ( V g) is applied to the Schottky gate to alter the Rashba coupling strength within the InAlAs-InGaAs 2DEG and thus modulate the spin state of the conduction electrons in the semiconductor channel. The combined effect of the tunnel barriers and the SOC can be used to achieve a spin transistor function. 31 Despite practical difficulties, it has been accepted that, in nanoscale devices, spin current can at least be generated at one end of the device and detected on the other. It is thus natural to conceive that SOC within a tunnel barrier can be utilized to achieve efficient spin filtering. Based on the notion of effective magnetic field, it will be straightforward to conceive that spin orbit coupling can be a natural, non-magnetic means of generating spin-polarized electron current. Spin orbit coupling (SOC) can be regarded as a form of effective magnetic field вЂseenвЂ™ by the spin of the electron in the rest frame. Jalil, in Introduction to the Physics of Nanoelectronics, 2012 Rashba spin orbit coupling spin field-effect transistor (FET)