Experimental Realization of Sensitivity Enhancement and Suppression with Exceptional Surfaces
Journal article, 2021

By preparing a sensor system around isolated exceptional points, one can obtain a great enhancement of the sensitivity benefiting from the non-Hermiticity. However, this comes at the cost of reduction of the flexibility of the system, which is critical for practical applications. By generalizing the exceptional points to exceptional surfaces, it has been theoretically proposed recently that enhanced sensitivity and flexibility can be combined. Here, an exceptional surface is experimentally demonstrated in a non-Hermitian photonic sensing system, which is composed of a whispering-gallery-mode microresonator and two nanofiber waveguides, resulting in a unidirectional coupling between two degenerate counter-propagating modes with an external optical isolator. The system is simple, robust, and can be easily operated around an exceptional surface. On the one hand, sensitivity enhancement is observed by monitoring the resonant frequency splitting caused by small perturbations. This demonstration of exceptional-surface-enhanced sensitivity paves the way for practical non-Hermitian sensing applications. On the other hand, the suppression of frequency splitting around the exceptional surface is also shown for the first time.

sensitivity enhancement

whispering gallery mode microresonators

exceptional surfaces

Author

Guo Qing Qin

Tsinghua University

Beijing Institute of Radio Measurement

Ran Ran Xie

Tsinghua University

Hao Zhang

Tsinghua University

Yun Qi Hu

Tsinghua University

Min Wang

Tsinghua University

Gui Qin Li

Tsinghua University

Haitan Xu

Southern University of Science and Technology

Fuchuan Lei

Chalmers, Microtechnology and Nanoscience (MC2), Photonics

Dong Ruan

Tsinghua University

Gui Lu Long

National Climate Center Beijing

Beijing Academy of Quantum Information Sciences

Frontier Science Center for Quantum Information

Tsinghua University

Laser and Photonics Reviews

1863-8880 (ISSN) 1863-8899 (eISSN)

Vol. In Press

Subject Categories

Atom and Molecular Physics and Optics

Other Physics Topics

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1002/lpor.202000569

More information

Latest update

5/4/2021 2