Robustness of entanglement as an indicator of topological phases in quantum walks
- 14 January 2020
- journal article
- research article
- Published by Optica Publishing Group in Optica
- Vol. 7 (1), 53-58
- https://doi.org/10.1364/optica.375388
Abstract
How to reveal topological phases and their boundaries is an intriguing issue in various systems. Entanglement, which plays fundamental role in quantum information, has been found profoundly related to the topological phases. However, experimentally exploring this relation is precluded by the limited ability to obtain the entanglement in many-body systems. In this work, we propose and experimentally demonstrate that the robustness of entanglement, quantified by the von Neumann entropy, can be used to reveal the topological phase with winding number $\mathcal{W}=1$ and topological phase with $\mathcal{W}=0$ in quantum walks. With the different robustness of entanglement against perturbations of a parameter, the phase boundaries between the distinct topological phases can be further determined. As a result, our work not only offers a new perspective for quantum walks, but also exhibits the deep connection between the entanglement and topological physics.
Keywords
Funding Information
- National Key Research and Development Program of China (2016YFA0302700, 2017YFA0304100)
- National Natural Science Foundation of China (11474267, 11774335, 11821404, 11874343, 61322506, 61725504)
- Key Research Program of Frontier Sciences, CAS (QYZDY-SSW-SLH003)
- Science Foundation of the CAS (ZDRW-XH-2019-1)
- Fundamental Research Funds for the Central Universities (WK2470000026)
- National Postdoctoral Program for Innovative Talents (BX201600146)
- China Postdoctoral Science Foundation (2017M612073)
- Anhui Initiative in Quantum Information Technologies (AHY020100, AHY060300)
This publication has 63 references indexed in Scilit:
- Observation of topological order in a superconducting doped topological insulatorNature Physics, 2010
- Observation of a large-gap topological-insulator class with a single Dirac cone on the surfaceNature Physics, 2009
- Topological Transition in a Non-Hermitian Quantum WalkPhysical Review Letters, 2009
- Mapping photonic entanglement into and out of a quantum memoryNature, 2008
- Quantum Spin-Hall Effect and Topologically Invariant Chern NumbersPhysical Review Letters, 2006
- Entanglement in a simple quantum phase transitionPhysical Review A, 2002
- Paired states of fermions in two dimensions with breaking of parity and time-reversal symmetries and the fractional quantum Hall effectPhysical Review B, 2000
- Macroscopic polarization as a geometric quantum phase: Many-body formulationPhysical Review B, 1994
- Quantum cryptography based on Bell’s theoremPhysical Review Letters, 1991
- Solitons in PolyacetylenePhysical Review Letters, 1979