ترغب بنشر مسار تعليمي؟ اضغط هنا

Large and Robust Charge-to-Spin Conversion in Sputtered Conductive WTex with Disorder

108   0   0.0 ( 0 )
 نشر من قبل Xiang Li
 تاريخ النشر 2020
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

Topological materials with large spin-orbit coupling and immunity to disorder-induced symmetry breaking show great promise for efficiently converting charge to spin. Here, we report that long-range disordered sputtered WTex thin films exhibit local chemical and structural order as those of Weyl semimetal WTe2 and conduction behavior that is consistent with semi-metallic Weyl fermion. We find large charge-to-spin conversion properties and electrical conductivity in thermally annealed sputtered WTex films that are comparable with those in crystalline WTe2 flakes. Besides, the strength of unidirectional spin Hall magnetoresistance in annealed WTex/Mo/CoFeB heterostructure is 5 to 20 times larger than typical SOT layer/ferromagnet heterostructures reported at room temperature. We further demonstrate room temperature damping-like SOT-driven magnetization switching of in-plane magnetized CoFeB. These large charge-to-spin conversion properties that are robust in the presence of long-range disorder and thermal annealing pave the way for industrial application of a new class of sputtered semimetals.

قيم البحث

اقرأ أيضاً

At interfaces with inversion symmetry breaking, Rashba effect couples the motion of electrons to their spin; as a result, spin-charge interconversion mechanism can occur. These interconversion mechanisms commonly exploit Rashba spin splitting at the Fermi level by spin pumping or spin torque ferromagnetic resonance. Here, we report evidence of significant photoinduced spin to charge conversion via Rashba spin splitting in an unoccupied state above the Fermi level at the Cu(111)/$alpha$-Bi$_{2}$O$_{3}$ interface. We predict an average Rashba coefficient of $1.72times 10^{-10}eV.m$ at 1.98 eV above the Fermi level, by fully relativistic first-principles analysis of the interfacial electronic structure with spin orbit interaction. We find agreement with our observation of helicity dependent photoinduced spin to charge conversion excited at 1.96 eV at room temperature, with spin current generation of $J_{s}=10^{6}A/m^{2}$. The present letter shows evidence of efficient spin-charge conversion exploiting Rashba spin splitting at excited states, harvesting light energy without magnetic materials or external magnetic fields.
We show here theoretically and experimentally that a Rashba-split electron state inside a ferromagnet can efficiently convert a dynamical spin accumulation into an electrical voltage. The effect is understood to stem from the Rashba splitting but wit h a symmetry linked to the magnetization direction. It is experimentally measured by spin pumping in a CoFeB/MgO structure where it is found to be as efficient as the inverse spin Hall effect at play when Pt replaces MgO, with the extra advantage of not affecting the damping in the ferromagnet.
Next-generation spintronic applications require material properties that can be hardly met by one material candidate. Here we demonstrate that by combining insulating and metallic magnets, enhanced spin-charge conversion and energy-efficient thermal spin currents can be realized. We develop a nanowire device consisting of an yttrium iron garnet and permalloy bi-layer. An interfacial temperature gradient drives the nanowire magnetization into auto-oscillations at gigahertz frequencies. Interfacial spin coupling and magnetoresistance of the permalloy layer translate spin dynamics into sizable microwave signals. The results show prospect for energy-efficient spintronic devices and present an experimental realization of magnon condensation in a heterogeneous magnetic system.
Layered transition-metal dichalcogenides (TMDs) family are gaining increasing importance due to their unique electronic band structures, promising interplay among light, valley (pseudospin), charge and spin degrees of freedom. They possess large intr insic spin-orbit interaction which make them most relevant for the emerging field of spin-orbitronics. Here we report on the conversion of spin current to charge current in MoS2 monolayer. Using spin pumping from a ferromagnetic layer (10 nm of cobalt) we find that the spin to charge conversion is highly efficient. Analysis in the frame of the inverse Rashba-Edelstein (RE) effect yields a RE length in excess of 4 nm at room temperature. Furthermore, owing to the semiconducting nature of MoS$_{2}$, it is found that back-gating allows electrical field control of the spin-relaxation rate of the MoS$_{2}$-metallic stack.
104 - Yang Li , Shi-jia Yang , Dali Sun 2020
b{eta}-PdBi2 has attracted much attention for its prospective ability to possess simultaneously topological surface and superconducting states due to its unprecedented spin-orbit interaction (SOC). Whereas most works have focused solely on investigat ing its topological surface states, the coupling between spin and charge degrees of freedom in this class of quantum material remains unexplored. Here we first report a study of spin-to-charge conversion in a b{eta}-PdBi2 ultrathin film grown by molecular beam epitaxy, utilizing a spin pumping technique to perform inverse spin Hall effect measurements. We find that the room temperature spin Hall angle of Fe/b{eta}-PdBi2, {theta}_SH=0.037. This value is one order of magnitude larger than that of reported conventional superconductors, and is comparable to that of the best SOC metals and topological insulators. Our results provide an avenue for developing superconductor-based spintronic applications.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا