- Physical Review Journals
All JournalsPhysics Magazine

Physical Review B

Export citation

Export citation

Choose format for download:

Download Citation
  • Letter

Truncation-dependent PT phase transition for the edge states of a two-dimensional non-Hermitian system

Dali Cheng1,2, Bo Peng2, Meng Xiao3, Xianfeng Chen2,4,5,6, Luqi Yuan2,*, and Shanhui Fan1

  • 1Ginzton Laboratory and Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA
  • 2State Key Laboratory of Advanced Optical Communication Systems and Networks, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
  • 3School of Physics and Technology, Center for Nanoscience and Nanotechnology, and Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, Wuhan University, Wuhan 430072, China
  • 4Shanghai Research Center for Quantum Sciences, Shanghai 201315, China
  • 5Jinan Institute of Quantum Technology, Jinan 250101, China
  • 6Collaborative Innovation Center of Light Manipulation and Applications, Shandong Normal University, Jinan 250358, China

  • *yuanluqi@sjtu.edu.cn
PDF

Phys. Rev. B 105, L201105 – Published 6 May, 2022

DOI: https://doi.org/10.1103/PhysRevB.105.L201105

Abstract

We consider a bulk system supporting parity and time reversal (PT) symmetry, and investigate how the PT phase transition of edge states is influenced by different truncations of the system. As an example, we study a two-dimensional PT-symmetric Su–Schrieffer–Heeger lattice with non-Hermitian onsite potentials. We find that when the truncation preserves certain symmetries of the bulk lattice, the edge states can remain in the PT-unbroken phase when the non-Hermitian onsite potentials are less than a nonzero critical value. On the other hand, when the truncation removes such symmetries, edge states with complex eigen-energies are observed for infinitesimal non-Hermitian onsite potentials. We develop an analytic theory to account for such behaviors. Our results are important in the manipulation of the gain and loss behaviors of edge states in non-Hermitian systems, with potential applications in the study of topological lasers, quantum sensors, and unidirectional invisibility.

View figure in article

Physics Subject Headings (PhySH)

Authorization Required

We need you to provide your credentials before accessing this content.
Article Available via CHORUS
Download Accepted Manuscript

Other Options

References (Subscription Required)

Outline

Information

Phys. Rev. B 105, L201105– Published 6 May, 2022
  • Received 16 January 2022
  • Revised 19 April 2022
  • Accepted 25 April 2022
Crossmark - Check for updates button

©2022 American Physical Society

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation