Tunneling Anomalous and Spin Hall Effects

Area of Science:

• Condensed matter physics
• Spintronics
• Materials science

Background:

• The anomalous Hall effect (AHE) is a phenomenon observed in magnetic materials.
• Spin Hall effect (SHE) involves spin accumulation due to spin-dependent scattering.
• Understanding interfacial effects is crucial for spintronic devices.

Purpose of the Study:

• To theoretically predict a novel anomalous Hall effect in magnetic-nonmagnetic tunnel junctions.
• To investigate the role of interfacial spin-orbit coupling in generating AHE and SHE.
• To explore anisotropic AHE and SHE in junctions with noncentrosymmetric barriers.

Main Methods:

• Theoretical prediction using first-principles calculations.
• Modeling of tunneling current through a heterojunction.
• Analysis of spin-dependent momentum filtering due to interfacial spin-orbit coupling.

Main Results:

• Predicted existence of anomalous Hall effect and spin Hall currents in the nonmagnetic electrode.
• Demonstrated that interfacial spin-orbit coupling induces skew tunneling without impurities.
• Showed that noncentrosymmetric barriers lead to anisotropic AHE and SHE, separable from bulk effects.

Conclusions:

• The proposed interfacial AHE offers a new route to study spin-orbit coupling.
• This effect can be utilized to quantify interfacial spin-orbit fields in various material systems.
• The findings have implications for designing advanced spintronic devices.