Light induced transitions of valley Chern numbers and flat bands in a non-twisted moire graphene-hexagonal boron nitride superlattice

TL;DR

This paper explores how light influences the topological properties and flat band phenomena in a non-twisted moire graphene-hexagonal boron nitride superlattice, revealing effects similar to twisted systems but with easier experimental access.

Contribution

It demonstrates that non-twisted moire systems exhibit rich topological and flat band physics under light, providing a more accessible platform to study moire phenomena.

Findings

Light induces topological phase transitions.

Flat bands are tunable by electromagnetic waves.

Rich topological phase diagram is revealed.

Abstract

Motivated by the rich topology and interesting quasi-band structure of twisted moire materials subjected to light, we study a non-twisted moire material under the influence of light. Our work is in part motivated by a desire to find an easier-to-synthesize platform that can help experimentally elucidate the interesting physics of moir\'e materials coupled to light. Similar to twisted moire materials, we uncover rich topology and interesting band flattening effects, which we summarize in relevant plots such as a topological phase diagram. Our work demonstrates that much of the interesting phenomenology of twisted moire materials under the influence of electromagnetic waves seems to be generically present even in more experimentally accessible untwisted moire platforms, which remain highly tunable by light.