Black hole mirages: electron lensing and Berry curvature effects in inhomogeneously tilted Weyl semimetals

TL;DR

This paper explores how spatially varying tilt profiles in Weyl semimetals can guide electron flow similarly to gravitational attraction, enabling novel device designs and revealing Berry curvature effects.

Contribution

It introduces a semiclassical approach to electron transport in tilted Weyl semimetals, drawing an analogy to gravity to facilitate device design and understanding of complex inhomogeneous systems.

Findings

Electron flow can be precisely guided by tilt profiles.

Semiclassical equations resemble gravitational attraction.

Berry curvature causes transverse motion related to spin precession.

Abstract

We study electronic transport in Weyl semimetals with spatially varying nodal tilt profiles. We find that the flow of electrons can be guided precisely by judiciously chosen tilt profiles. In a broad regime of parameters, we show that electron flow is described well by semiclassical equations of motion similar to the ones governing gravitational attraction. This analogy provides a physically transparent tool for designing tiltronic devices like electronic lenses. The analogy to gravity circumvents the notoriously difficult full-fledged description of inhomogeneous solids. A comparison to microscopic lattice simulations shows that it is only valid for trajectories sufficiently far from analogue black holes. We finally comment on the Berry curvature-driven transverse motion and relate the latter to spin precession physics.