Generating topological optical flux lattices for ultracold atoms by modulated Raman and radio-frequency couplings

TL;DR

This paper presents a method to create optical flux lattices with topological properties in ultracold atoms using modulated Raman and rf fields, enabling exploration of various quantum phases.

Contribution

It introduces a dynamic scheme to generate topological optical flux lattices with tunable phases, including insulator, topological insulator, and semimetal, in a cold-atom setup.

Findings

Realization of three distinct phases at unit filling.

Appearance of nearly nondispersive bands in the topological phase.

Validation of the scheme through Floquet quasienergy analysis.

Abstract

We propose a scheme to dynamically generate optical flux lattices with nontrivial band topology using amplitude-modulated Raman lasers and radio-frequency (rf) magnetic fields. By tuning the strength of Raman and rf fields, three distinct phases are realized at unit filling for a unit cell. Respectively, these three phases correspond to normal insulator, topological Chern insulator, and semimetal. Nearly nondispersive bands are found to appear in the topological phase, which promises opportunities for investigating strongly correlated quantum states within a simple cold-atom setup. The validity of our proposal is confirmed by comparing the Floquet quasienergies from the evolution operator with the spectrum of the effective Hamiltonian.