Uncover Topology by Quantum Quench Dynamics
Abstract
Topological quantum states are characterized by nonlocal invariants, and their detection is intrinsically challenging. Various strategies have been developed to study topological Hamiltonians through their equilibrium states. We present a fundamentally new, high-precision dynamical approach, revealing topology through the unitary evolution after a quench from a topological trivial initial state with a two-dimensional Chern band realized in an ultracold Rb atom gas. The emerging ring structure in the spin dynamics uniquely determines the Chern number for the post-quench band and enables probing the full phase diagram of the band topology with high precision. Besides, we also measure the topological band gap and the domain wall structure dynamically formed in the momentum space during the long-term evolution. Our dynamical approach provides a way towards observing a universal bulk-ring correspondence, and has broad applications in exploring topological quantum matter.
Cite
@article{arxiv.1804.08226,
title = {Uncover Topology by Quantum Quench Dynamics},
author = {Wei Sun and Chang-Rui Yi and Bao-Zong Wang and Wei-Wei Zhang and Barry C. Sanders and Xiao-Tian Xu and Zong-Yao Wang and Jörg Schmiedmayer and Youjin Deng and Xiong-Jun Liu and Shuai Chen and Jian-Wei Pan},
journal= {arXiv preprint arXiv:1804.08226},
year = {2018}
}
Comments
9 pages, 5 figures for main text and 12 pages for supplementary material