PT-Symmetric Topological Edge-Gain Effect

Alex Y. Song, Xiao-Qi Sun, Avik Dutt, Momchil Minkov, Casey Wojcik, Haiwen Wang, Ian A. D. Williamson, Meir Orenstein, and Shanhui Fan
Phys. Rev. Lett. 125, 033603 – Published 14 July 2020
PDFHTMLExport Citation

Abstract

We demonstrate a non-Hermitian topological effect that is characterized by having complex eigenvalues only in the edge states of a topological material, despite the fact that the material is completely uniform. Such an effect can be constructed in any topological structure formed by two gapped subsystems, e.g., a quantum spin-Hall system, with a suitable non-Hermitian coupling between the spins. The resulting complex-eigenvalued edge state is robust against defects due to the topological protection. In photonics, such an effect can be used for the implementation of topological lasers, in which a uniform pumping provides gain only in the edge lasing state. Furthermore, such a topological lasing model is reciprocal and is thus compatible with standard photonic platforms.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 24 October 2019
  • Accepted 23 June 2020

DOI:https://doi.org/10.1103/PhysRevLett.125.033603

© 2020 American Physical Society

Physics Subject Headings (PhySH)

Atomic, Molecular & Optical

Authors & Affiliations

Alex Y. Song1, Xiao-Qi Sun2, Avik Dutt1, Momchil Minkov1, Casey Wojcik1, Haiwen Wang3, Ian A. D. Williamson1, Meir Orenstein4, and Shanhui Fan1,*

  • 1Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA
  • 2Department of Physics, Stanford University, Stanford, California 94305, USA
  • 3Department of Applied Physics, Stanford University, Stanford, California 94305, USA
  • 4Department of Electrical Engineering, Technion—Israel Institute of Technology, Technion City, Haifa 3200003, Israel

  • *shanhui@stanford.edu

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 125, Iss. 3 — 17 July 2020

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×