Exceptional-point-encirclement emulation tailoring: multidimensional asymmetric switching of all-fiber devices

Kang Li; Yuchen Zhang; Siwei Wang; Jian Wang

doi:10.1038/s41377-025-02144-x

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Exceptional-point-encirclement emulation tailoring: multidimensional asymmetric switching of all-fiber devices

Original Articles

- Exceptional-point-encirclement emulation tailoring: multidimensional asymmetric switching of all-fiber devices
- Light: Science & Applications Vol. 15, Issue 1, Pages: 119-129(2026)
- Affiliations：
  
  1.Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei, China
  2.Hubei Optical Fundamental Research Center, Wuhan, Hubei, China
  3.Optics Valley Laboratory, Hubei, Wuhan, Hubei, China
- Author bio：
  
  Jian Wang (jwang@hust.edu.cn)
- Funds：
- DOI：10.1038/s41377-025-02144-x
  CLC：
- Received：10 March 2025，
  
  Revised：2025-11-12，
  
  Accepted：23 November 2025，
  
  Published Online：01 January 2026，
  
  Published：31 January 2026
- Accepted：
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Li, K. et al. Exceptional-point-encirclement emulation tailoring: multidimensional asymmetric switching of all-fiber devices. Light: Science & Applications, 15, 119-129 (2026).
DOI：

Li, K. et al. Exceptional-point-encirclement emulation tailoring: multidimensional asymmetric switching of all-fiber devices. Light: Science & Applications, 15, 119-129 (2026). DOI： 10.1038/s41377-025-02144-x.

摘要

Abstract

In non-Hermitian systems

the dynamic encircling of exceptional points (EPs) engenders intriguing chiral phenomena

where the resultant state characteristics are intrinsically dependent upon the encircling handedness. An ingenious approach using simple leaky optical elements has been presented to emulate this chiral behavior without physically encircling an EP. This innovative simplification of EP properties enables a more straightforward implementation of asymmetric switching of polarization and path. Given that photons inherently possess multiple physical degrees of freedom

the research focus has shifted from single-dimensional to multidimensional asymmetric switching. Hence

there is a fundamental challenge of how to achieve multidimensional asymmetric switching through a simple and universally applicable architecture. Here

we propose and experimentally demonstrate a novel topology-optimized architecture

termed EP-encirclement emulation tailoring

enabling multidimensional asymmetric switching. Theoretical analysis reveals that our architecture eliminates the 3-dB inherent loss in conventional architecture by replacing couplers with (de)multiplexers. Building upon this architecture

we harness all-fiber devices to implement a high-performance asymmetric switching of polarization

mode

and orbital angular momentum (OAM). To our knowledge

this is the first experimental demonstration of asymmetric OAM switching to date. Our work provides an efficient topology architecture for emulating dynamic EP encirclement

paving the way for universal and flexible asymmetric switching devices.

关键词

Keywords

references

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