Simulating and exploring Weyl semimetal physics with cold atoms in a two-dimensional optical lattice

TL;DR

This paper proposes a feasible method to simulate Weyl semimetal physics using ultracold atoms in a 2D optical lattice with spin-orbit coupling, enabling exploration of topological properties and experimental detection of Weyl points.

Contribution

It introduces a scheme to realize and study Weyl semimetal physics in a 2D optical lattice, making experimental investigation more practical.

Findings

Simulation of three-dimensional Weyl semimetals in 2D lattice

Detection of Weyl points via atomic transfer fractions

Measurement of topological invariants through particle pumping

Abstract

We propose a scheme to simulate and explore Weyl semimetal physics with ultracold fermionic atoms in a two-dimensional square optical lattice subjected to experimentally realizable spin-orbit coupling and an artificial dimension from an external parameter space, which may increase experimental feasibility compared with the cases in three dimensional optical lattices. It is shown that this system with a tight-binding model is able to describe essentially three-dimensional Weyl semimetals with tunable Weyl points. The relevant topological properties are also addressed by means of the Chern number and the gapless edge states. Furthermore, we illustrate that the mimicked Weyl points can be experimentally detected by measuring the atomic transfer fractions in a Bloch-Zener oscillation, and the characteristic topological invariant can be measured with the particle pumping approach.