Direct Detection of Axion-Like Particles in Bismuth-Based Topological Insulators

TL;DR

This paper explores the potential of Bismuth-based topological insulators for direct detection of axion-like particles, highlighting their high sensitivity and unique advantages over other materials in dark matter searches.

Contribution

It demonstrates that topological insulators can serve as effective detectors for axion-like particles, offering comparable sensitivity to superconductors and semiconductors, especially in thin film form.

Findings

Topological insulators show strong sensitivity to axion detection.

Thin films of topological insulators can match superconductors in sensitivity.

Electronic systems can probe sub-GeV and ultra-light dark matter.

Abstract

In recent years a new field emerged in dark matter community and immediately attracted a multitude of theoriests and experimentalists, that of light dark matter direct detection in electronic systems. The phenomenon is similar with nuclear recoil in elastic scattering between dark matter and nucleus but with different kinematics. Due to the small energy gap, the electronic system can probe sub-GeV dark matter rather than nucleus target. In particular the absorption into materials can even detect ultra-light dark matter within mass around meV. In terms of the equivalence between optical conductivity and absorption cross section, axion detection can be computed in Bismuth-based topological insulators. It is found that topological insulator has strong sensitivity on axion and provides a complementary direct detection to superconductor and semiconductors. The novelty of topological insulator is that the thin film could even obtain the same sensitivity as superconductor.