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Updated: Aug 11, 2025

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
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Published on: June 28, 2018

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Optical bulk-boundary dichotomy in a quantum spin Hall insulator.

Junfeng Han1, Pengcheng Mao2, Hailong Chen3

  • 1Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (Ministry of Education), School of Physics, Beijing Institute of Technology, Beijing 100081, China; Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314000, China; Beijing Key Laboratory of Nanophotonics & Ultrafine Optoelectronic Systems, Beijing Institute of Technology, Beijing 100081, China.

Science Bulletin
|February 5, 2023
PubMed
Summary

We reveal optical distinctions between bulk and boundary states in topological quantum materials using infrared spectroscopy. This study highlights unique optical properties and long carrier lifetimes of boundary states in Bi4Br4, a room-temperature quantum spin Hall insulator.

Keywords:
Bi(4)Br(4)Edge statesMid-infrared absorption micro-spectroscopyPump–probe micro-spectroscopyQuantum spin Hall effectTopological insulator

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