Lithography defined semiconductor moires with anomalous in-gap quantum Hall states

TL;DR

This paper introduces lithography-defined semiconductor moire superlattices with tunable quantum properties, demonstrating anomalous in-gap states in InAs quantum wells, paving the way for advanced quantum devices.

Contribution

It presents a novel lithography-based method to create scalable, reproducible semiconductor moire superlattices with designable electronic parameters.

Findings

Observation of strong anomalous in-gap states in InAs quantum wells.

Demonstration of tunable quantum transport properties in lithography-defined moire structures.

Potential for integration into quantum information and microelectronics technologies.

Abstract

Quantum materials and phenomena have attracted great interest for their potential applications in next-generation microelectronics and quantum-information technologies. In one especially interesting class of quantum materials, moire superlattices (MSL) formed by twisted bilayers of 2D materials, a wide range of novel phenomena are observed. However, there exist daunting challenges such as reproducibility and scalability of utilizing 2D MSLs for microelectronics and quantum technologies due to their exfoliate-tear-stack method. Here, we propose lithography defined semiconductor moires superlattices, in which three fundamental parameters, electron-electron interaction, spin-orbit coupling, and band topology, are designable. We experimentally investigate quantum transport properties in a moire specimen made in an InAs quantum well. Strong anomalous in-gap states are observed within the same integer quantum Hall state. Our work opens up new horizons for studying 2D quantum-materials phenomena in semiconductors featuring superior industry-level quality and state-of-the-art technologies, and they may potentially enable new quantum information and microelectronics technologies.