Realization of Exceptional Points Along a Synthetic Orbital Angular Momentum Dimension

Overview

Journal Sci Adv

Specialties Biology
Science

Date 2023 Jan 25

PMID 36696496

Authors

Mu Yang

Hao-Qing Zhang

Yu-Wei Liao

Zheng-Hao Liu

Zheng-Wei Zhou

Xing-Xiang Zhou

Jin-Shi Xu

Yong-Jian Han

Chuan-Feng Li

Guang-Can Guo

Affiliations

Soon will be listed here.

Abstract

Exceptional points (EPs), at which more than one eigenvalue and eigenvector coalesce, are unique spectral features of non-Hermiticity (NH) systems. They exist widely in open systems with complex energy spectra. We experimentally demonstrate the appearance of paired EPs in a periodical-driven degenerate optical cavity along the synthetic orbital angular momentum dimension with a tunable parameter. The complex-energy band structures and the key features of EPs, i.e., their bulk Fermi arcs, parity-time symmetry breaking transition, energy swapping, and half-integer band windings, are directly observed by detecting the wavefront angle-resolved transmission spectrum. Our results demonstrate the flexibility of using the photonic synthetic dimensions to implement NH systems beyond their geometric dimension and EP-based sensing.

Citing Articles

Observing non-Hermiticity induced chirality breaking in a synthetic Hall ladder.

Ye R, He Y, Li G, Wang L, Wu X, Qiao X Light Sci Appl. 2025; 14(1):39.

PMID: 39774943 PMC: 11707151. DOI: 10.1038/s41377-024-01700-1.

References

Dutt A, Minkov M, Lin Q, Yuan L, Miller D, Fan S . Experimental band structure spectroscopy along a synthetic dimension. Nat Commun. 2019; 10(1):3122. PMC: 6635488. DOI: 10.1038/s41467-019-11117-9. View

Zhou H, Peng C, Yoon Y, Hsu C, Nelson K, Fu L . Observation of bulk Fermi arc and polarization half charge from paired exceptional points. Science. 2018; 359(6379):1009-1012. DOI: 10.1126/science.aap9859. View

Miri M, LiKamWa P, Christodoulides D . Large area single-mode parity-time-symmetric laser amplifiers. Opt Lett. 2012; 37(5):764-6. DOI: 10.1364/OL.37.000764. View

Zhang X, Ding K, Zhou X, Xu J, Jin D . Experimental Observation of an Exceptional Surface in Synthetic Dimensions with Magnon Polaritons. Phys Rev Lett. 2019; 123(23):237202. DOI: 10.1103/PhysRevLett.123.237202. View

Wu Y, Liu W, Geng J, Song X, Ye X, Duan C . Observation of parity-time symmetry breaking in a single-spin system. Science. 2019; 364(6443):878-880. DOI: 10.1126/science.aaw8205. View

Arnaud J . Degenerate Optical Cavities. II: Effect of Misalignments. Appl Opt. 2010; 8(9):1909-17. DOI: 10.1364/AO.8.001909. View

Hodaei H, Hassan A, Wittek S, Garcia-Gracia H, El-Ganainy R, Christodoulides D . Enhanced sensitivity at higher-order exceptional points. Nature. 2017; 548(7666):187-191. DOI: 10.1038/nature23280. View

Weidemann S, Kremer M, Longhi S, Szameit A . Topological triple phase transition in non-Hermitian Floquet quasicrystals. Nature. 2022; 601(7893):354-359. PMC: 8770143. DOI: 10.1038/s41586-021-04253-0. View

Hodaei H, Miri M, Heinrich M, Christodoulides D, Khajavikhan M . Parity-time-symmetric microring lasers. Science. 2014; 346(6212):975-8. DOI: 10.1126/science.1258480. View

10.

Yuan L, Lin Q, Zhang A, Xiao M, Chen X, Fan S . Photonic Gauge Potential in One Cavity with Synthetic Frequency and Orbital Angular Momentum Dimensions. Phys Rev Lett. 2019; 122(8):083903. DOI: 10.1103/PhysRevLett.122.083903. View

11.

Wang K, Dutt A, Yang K, Wojcik C, Vuckovic J, Fan S . Generating arbitrary topological windings of a non-Hermitian band. Science. 2021; 371(6535):1240-1245. DOI: 10.1126/science.abf6568. View

12.

Zhong Q, Khajavikhan M, Christodoulides D, El-Ganainy R . Winding around non-Hermitian singularities. Nat Commun. 2018; 9(1):4808. PMC: 6237871. DOI: 10.1038/s41467-018-07105-0. View

13.

Cheng Z, Liu Z, Li Q, Zhou Z, Xu J, Li C . Flexible degenerate cavity with ellipsoidal mirrors. Opt Lett. 2019; 44(21):5254-5257. DOI: 10.1364/OL.44.005254. View

14.

Arnaud J . Degenerate optical cavities. Appl Opt. 2010; 8(1):189-95. DOI: 10.1364/AO.8.000189. View

15.

Doppler J, Mailybaev A, Bohm J, Kuhl U, Girschik A, Libisch F . Dynamically encircling an exceptional point for asymmetric mode switching. Nature. 2016; 537(7618):76-79. DOI: 10.1038/nature18605. View

16.

Okuma N, Kawabata K, Shiozaki K, Sato M . Topological Origin of Non-Hermitian Skin Effects. Phys Rev Lett. 2020; 124(8):086801. DOI: 10.1103/PhysRevLett.124.086801. View

17.

Adiyatullin A, Upreti L, Lechevalier C, Evain C, Copie F, Suret P . Topological Properties of Floquet Winding Bands in a Photonic Lattice. Phys Rev Lett. 2023; 130(5):056901. DOI: 10.1103/PhysRevLett.130.056901. View

18.

Hokmabadi M, Schumer A, Christodoulides D, Khajavikhan M . Non-Hermitian ring laser gyroscopes with enhanced Sagnac sensitivity. Nature. 2019; 576(7785):70-74. DOI: 10.1038/s41586-019-1780-4. View

19.

Yoon J, Choi Y, Hahn C, Kim G, Song S, Yang K . Time-asymmetric loop around an exceptional point over the full optical communications band. Nature. 2018; 562(7725):86-90. DOI: 10.1038/s41586-018-0523-2. View

20.

Lai Y, Lu Y, Suh M, Yuan Z, Vahala K . Observation of the exceptional-point-enhanced Sagnac effect. Nature. 2019; 576(7785):65-69. DOI: 10.1038/s41586-019-1777-z. View