Measurement of spin Chern numbers in quantum simulated topological insulators

The topology of quantum systems has become a topic of great interest since the discovery of topological insulators. However, as a hallmark of the topological insulators, the spin Chern number has not yet been experimentally detected. The challenge to directly measure this topological invariant lies...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2021-07
Main Authors: Qing-Xian Lv, Yan-Xiong, Du, Zhen-Tao, Liang, Hong-Zhi, Liu, Jia-Hao, Liang, Lin-Qing, Chen, Li-Ming, Zhou, Shan-Chao, Zhang, Dan-Wei, Zhang, Bao-Quan Ai, Yan, Hui, Shi-Liang, Zhu
Format: Article
Language:English
Subjects:
Atomic properties
Cold atoms
Cold spinning
Topological insulators
Topology
Wave functions
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The topology of quantum systems has become a topic of great interest since the discovery of topological insulators. However, as a hallmark of the topological insulators, the spin Chern number has not yet been experimentally detected. The challenge to directly measure this topological invariant lies in the fact that this spin Chern number is defined based on artificially constructed wavefunctions. Here we experimentally mimic the celebrated Bernevig-Hughes-Zhang model with cold atoms, and then measure the spin Chern number with the linear response theory. We observe that, although the Chern number for each spin component is ill defined, the spin Chern number measured by their difference is still well defined when both energy and spin gaps are non-vanished.
ISSN:2331-8422
DOI:10.48550/arxiv.2107.13110