Related papers: Observation of a symmetry-protected topological phase in external magnetic fields

Observation of a symmetry-protected topological phase in external magnetic fields

URL: http://arxiv.org/abs/2208.05357v2
Date: Thu, 11 Aug 2022 02:55:37 GMT
Title: Observation of a symmetry-protected topological phase in external magnetic fields
Authors: Zhihuang Luo, Wenzhao Zhang, Xinfang Nie, Dawei Lu
Abstract summary: We report the real-space observation of a symmetry-protected topological phase with interacting nuclear spins. We probe the interaction-induced transition between two topologically distinct phases, both of which are classified by many-body Chern numbers. Our findings enable direct characterization of topological features of quantum many-body states through gradually decreasing the strength of the introduced external fields.
Score: 1.4515101661933258
License: http://creativecommons.org/publicdomain/zero/1.0/
Abstract: Topological phases have greatly improved our understanding of modern conception of phases of matter that go beyond the paradigm of symmetry breaking and are not described by local order parameters. Instead, characterization of topological phases requires the robust topological invariants, whereas measuring these global quantities presents an outstanding challenge for experiments, especially in interacting systems. Here we report the real-space observation of a symmetry-protected topological phase with interacting nuclear spins, and probe the interaction-induced transition between two topologically distinct phases, both of which are classified by many-body Chern numbers obtained from the dynamical response to the external magnetic fields. The resulting value of Chern number ($\bar{\mathcal{C}h} = 1.958 \pm 0.070$) demonstrates the robust ground state degeneracy, and also determines the number of nontrivial edge states. Our findings enable direct characterization of topological features of quantum many-body states through gradually decreasing the strength of the introduced external fields.