Speaker
Description
Magnetization in solids arises from both orbital and spin degrees of freedom. While spin-related effects, such as the spin Hall and inverse spin Hall effects, have been widely considered the dominant mechanisms in magnetoelectric phenomena, recent experimental evidence suggests a much more significant role for orbital contributions than previously expected. This has led to the development of the concept of the orbital Hall effect.
Here, we present an alternative perspective on orbital physics in metals and semiconductors subjected to charge currents. It is well established that a non-equilibrium orbital magnetic moment can emerge in conductors due to skew scattering from asymmetric impurities. We highlight that a similar skew-scattering mechanism can also be induced by conductor boundaries, even in the absence of special impurities.
Specifically, we propose that a high-quality, flat interface can act as a long-range skew scatterer for charged quasiparticles. When an electric current flows parallel to the interface, an imbalance in clockwise and counterclockwise scattering leads to a net orbital magnetization. This magnetization is strongest at the interface and decays linearly in the perpendicular direction. We suggest that this effect can be experimentally detected through spatially resolved Kerr effect measurements at distances up to the electron phase coherence length from the interface. Unlike the orbital Hall and orbital Edelstein effects, this phenomenon does not rely on bulk inversion symmetry breaking and is fundamentally distinct from Hall physics.
