Revealing the hidden Dirac gap in a topological antiferromagnet using Floquet-Bloch manipulation
Abstract
Manipulating solids using the time-periodic drive of a laser pulse is a promising route to generate new phases of matter. Whether such `Floquet-Bloch' manipulation can be achieved in topological magnetic systems with disorder has so far been unclear. In this work, we realize Floquet-Bloch manipulation of the Dirac surface-state mass of the topological antiferromagnet (AFM) MnBiTe. Using time- and angle-resolved photoemission spectroscopy (tr-ARPES), we show that opposite helicities of mid-infrared circularly polarized light result in substantially different Dirac mass gaps in the AFM phase, despite the equilibrium Dirac cone being massless. We explain our findings in terms of a Dirac fermion with a random mass. Our results underscore Floquet-Bloch manipulation as a powerful tool for controlling topology even in the presence of disorder, and for uncovering properties of materials that may elude conventional probes.
Cite
@article{arxiv.2405.16432,
title = {Revealing the hidden Dirac gap in a topological antiferromagnet using Floquet-Bloch manipulation},
author = {Nina Bielinski and Rajas Chari and Julian May-Mann and Soyeun Kim and Jack Zwettler and Yujun Deng and Anuva Aishwarya and Subhajit Roychowdhury and Chandra Shekhar and Makoto Hashimoto and Donghui Lu and Jiaqiang Yan and Claudia Felser and Vidya Madhavan and Zhi-Xun Shen and Taylor L. Hughes and Fahad Mahmood},
journal= {arXiv preprint arXiv:2405.16432},
year = {2024}
}