Skyrmion-electron interaction in the separated spin-up and spin-down quantum hydrodynamics approach

Abstract

The Berry gauge field associated with adiabatic quantum evolution represents a very interesting area of research, especially for the description of non-relativistic fermions coupled to a skyrmion texture. We construct a quantum hydrodynamics model that describes the electron-skyrmion interactions, with separate descriptions of spin-up and spin-down electrons as two different fluids. The quantum effects, represented by the quantum Bohm potential, are taken into account. We investigate the electron gas moving in a smooth magnetic texture, where the magnetic moments adjust to the local magnetization direction of the skyrmion, and derive the equations of motion and evolution of spin density for two fluids of electrons in the emergent gauge fields. Applying the separated spin evolution quantum hydrodynamics to the 2D electron gas, traveling on the background of the Berry gauge field in plane samples, located in an external magnetic field, we predict a wave of a new kind in the electron gas. This novel wave appears as an influence of emergent fields and quantum effects.