- Letter
- Open Access
Pseudo-Hermiticity protects the energy-difference conservation in the scattering
Phys. Rev. Research 5, L042005 – Published 4 October, 2023
DOI: https://doi.org/10.1103/PhysRevResearch.5.L042005
Abstract
Symmetry plays a fundamentally important role in physics. In this work, we find a conservation law, , which is valid for any non-Hermitian scattering center . As a result, the reflections and transmissions of a non-Hermitian system and its Hermitian conjugation system satisfy the conservation law , instead of the energy conservation law that applies to incoming and outgoing waves in a Hermitian system. Consequently, the pseudo-Hermiticity of a non-Hermitian system ensures an energy-difference conservation. Furthermore, we demonstrate that the energy-difference conservation is respectively valid and invalid in two prototypical anti--symmetric systems, where the energy-difference conservation is protected by the pseudo-Hermiticity. Our findings provide profound insight into the conservation law, the pseudo-Hermiticity, and the anti--symmetry in non-Hermitian systems.
Physics Subject Headings (PhySH)
Article Text
Supplemental Material
References (133)
- N. Moiseyev, Non-Hermitian Quantum Mechanics (Cambridge University Press, Cambridge, England, 2011).
- L. Jin and Z. Song, Wavepacket Dynamics in a non-Hermitian symmetric tight-binding chain, Commun. Theor. Phys. 54, 73 (2010).
- Z. Lin, H. Ramezani, T. Eichelkraut, T. Kottos, H. Cao, and D. N. Christodoulides, Unidirectional invisibility induced by -symmetric periodic structures, Phys. Rev. Lett. 106, 213901 (2011).
- D. Leykam, V. V. Konotop, and A. S. Desyatnikov, Discrete vortex solitons and parity time symmetry, Opt. Lett. 38, 371 (2013).
- L. Feng, Y. L. Xu, W. S. Fegadolli, M. H. Lu, J. E. B. Oliveira, V. R. Almeida, Y. F. Chen, and A. Scherer, Experimental demonstration of a unidirectional reflectionless parity-time metamaterial at optical frequencies, Nat. Mater. 12, 108 (2013).
- H. Ramezani, H. K. Li, Y. Wang, and X. Zhang, Unidirectional spectral singularities, Phys. Rev. Lett. 113, 263905 (2014).
- R. Fleury, D. Sounals, and A. Alù, An invisible acoustic sensor based on parity-time symmetry, Nat. Commun. 6, 5905 (2015).
- P. Wang, L. Jin, G. Zhang, and Z. Song, Wave emission and absorption at spectral singularities, Phys. Rev. A 94, 053834 (2016).
- V. V. Konotop and D. A. Zezyulin, Phase transition through the splitting of self-dual spectral singularity in optical potentials, Opt. Lett. 42, 5206 (2017).
- D. Leykam, S. Flach, and Y. D. Chong, Flat bands in lattices with non-Hermitian coupling, Phys. Rev. B 96, 064305 (2017).
- D. Leykam, K. Y. Bliokh, C. Huang, Y. D. Chong, and F. Nori, Edge modes, degeneracies, and topological numbers in non-Hermitian systems, Phys. Rev. Lett. 118, 040401 (2017).
- H. Ramezani, P. K. Jha, Y. Wang, and X. Zhang, Nonreciprocal localization of photons, Phys. Rev. Lett. 120, 043901 (2018).
- Y.-X. Wang and A. A. Clerk, Non-Hermitian dynamics without dissipation in quantum systems, Phys. Rev. A 99, 063834 (2019).
- V. V. Konotop, E. Lakshtanov, and B. Vainberg, Designing lasing and perfectly absorbing potentials, Phys. Rev. A 99, 043838 (2019).
- D. A. Zezyulin and V. V. Konotop, Universal form of arrays with spectral singularities, Opt. Lett. 45, 3447 (2020).
- L. Xiao, T. S. Deng, K. K. Wang, G. Y. Zhu, Z. Wang, W. Yi, and P. Xue, Observation of non-Hermitian bulk-boundary correspondence in quantum dynamics, Nat. Phys. 16, 761 (2020).
- W. Gou, T. Chen, D. Xie, T. Xiao, T.-S. Deng, B. Gadway, W. Yi, and B. Yan, Tunable nonreciprocal quantum transport through a dissipative Aharonov-Bohm ring in ultracold atoms, Phys. Rev. Lett. 124, 070402 (2020).
- H. Ramezani, Spectral singularities with directional sensitivity, Phys. Rev. A 103, 043516 (2021).
- K. Wang, L. Xiao, J. C. Budich, W. Yi, and P. Xue, Simulating exceptional non-Hermitian metals with single-photon interferometry, Phys. Rev. Lett. 127, 026404 (2021).
- Q. Liang, D. Xie, Z. Dong, H. Li, H. Li, B. Gadway, W. Yi, and B. Yan, Dynamic signatures of non-Hermitian skin effect and topology in ultracold atoms, Phys. Rev. Lett. 129, 070401 (2022).
- C. Yuce and H. Ramezani, Coexistence of extended and localized states in the one-dimensional non-Hermitian Anderson model, Phys. Rev. B 106, 024202 (2022).
- Y. Zuo, R. Huang, L.-M. Kuang, X.-W. Xu, and H. Jing, Loss-induced suppression, revival, and switch of photon blockade, Phys. Rev. A 106, 043715 (2022).
- X. Chen, H. Wang, J. Li, K.-y. Wong, and D. Lei, Scattering asymmetry and circular dichroism in coupled PT-symmetric chiral nanoparticles, Nanophotonics 11, 2159 (2022).
- S. Longhi and E. Pinotti, Non-Hermitian invisibility in tight-binding lattices, Phys. Rev. B 106, 094205 (2022).
- Z. Sakotic, P. Stankovic, V. Bengin, A. Krasnok, A. Alù, and N. Jankovic, Non-Hermitian control of topological scattering singularities emerging from bound states in the continuum, Laser Photonics Rev. 17, 2200308 (2023).
- H. S. Xu, L. C. Xie, and L. Jin, High-order spectral singularity, Phys. Rev. A 107, 062209 (2023).
- Y. D. Chong, L. Ge, H. Cao, and A. D. Stone, Coherent perfect absorbers: Time-reversed lasers, Phys. Rev. Lett. 105, 053901 (2010).
- S. Longhi, PT-symmetric laser absorber, Phys. Rev. A 82, 031801(R) (2010).
- W. Wan, Y. Chong, L. Ge, H. Noh, A. D. Stone, and H. Cao, Time-reversed lasing and interferometric control of absorption, Science 331, 889 (2011).
- Y. Sun, W. Tan, H.-Q. Li, J. Li, and H. Chen, Experimental demonstration of a coherent perfect absorber with PT phase transition, Phys. Rev. Lett. 112, 143903 (2014).
- T. Roger, S. Vezzoli, E. Bolduc, J. Valente, J. J. F. Heitz, J. Jeffers, C. Soci, J. Leach, C. Couteau, N. I. Zheludev, and D. Faccio, Coherent perfect absorption in deeply subwavelength films in the single-photon regime, Nat. Commun. 6, 7031 (2015).
- D. G. Baranov, A. Krasnok, T. Shegai, A. Alù, and Y. Chong, Coherent perfect absorbers: Linear control of light with light, Nat. Rev. Mater. 2, 17064 (2017).
- D. Zhang, X.-Q. Luo, Y.-P. Wang, T.-F. Li, and J. Q. You, Observation of the exceptional point in cavity magnon-polaritons, Nat. Commun. 8, 1368 (2017).
- W. R. Sweeney, C. W. Hsu, S. Rotter, and A. D. Stone, Perfectly absorbing exceptional points and Chiral absorbers, Phys. Rev. Lett. 122, 093901 (2019).
- C. Wang, W. R. Sweeney, A. D. Stone, and L. Yang, Coherent perfect absorption at an exceptional point, Science 373, 1261 (2021).
- J. Luo, H. Chu, R. Peng, M. Wang, J. Li, and Y. Lai, Ultra-broadband reflectionless Brewster absorber protected by reciprocity, Light Sci. Appl. 10, 89 (2021).
- S. Soleymani, Q. Zhong, M. Mokim, S. Rotter, R. El-Ganainy, and Ş. K. Özdemir, Chiral and degenerate perfect absorption on exceptional surfaces, Nat. Commun. 13, 599 (2022).
- S. Suwunnarat, Y. Tang, M. Reisner, F. Mortessagne, U. Kuhl, and T. Kottos, Non-linear coherent perfect absorption in the proximity of exceptional points, Commun. Phys. 5, 5 (2022).
- J. Hou, J. Lin, J. Zhu, G. Zhao, Y. Chen, F. Zhang, Y. Zheng, X. Chen, Y. Cheng, L. Ge, and W. Wan, Self-induced transparency in a perfectly absorbing chiral second-harmonic generator, PhotoniX 3, 22 (2022).
- M. Liu, W. Chen, G. Hu, S. Fan, D. N. Christodoulides, C. Zhao, and C.-W. Qiu, Spectral phase singularity and topological behavior in perfect absorption, Phys. Rev. B 107, L241403 (2023).
- B. Peng, Ş. K. Özdemir, S. Rotter, H. Yilmaz, M. Liertzer, F. Monifi, C. M. Bender, F. Nori, and L. Yang, Loss-induced suppression and revival of lasing, Science 346, 328 (2014).
- H. Hodaei, A. U. Hassan, S. Wittek, H. Garcia-Gracia, R. El-Ganainy, D. N. Christodoulides, and M. Khajavikhan, Enhanced sensitivity at higher-order exceptional points, Nature (London) 548, 187 (2017).
- W. Chen, Ş. K. Özdemir, G. Zhao, J. Wiersig, and L. Yang, Exceptional points enhance sensing in an optical microcavity, Nature (London) 548, 192 (2017).
- H.-K. Lau and A. A. Clerk, Fundamental limits and nonreciprocal approaches in non-Hermitian quantum sensing,xbrk Nat. Commun. 9, 4320 (2018).
- C. Chen, L. Jin, and R.-B. Liu, Sensitivity of parameter estimation near the exceptional point of a non-Hermitian system, New J. Phys. 21, 083002 (2019).
- M. P. Hokmabadi, A. Schumer, D. N. Christodoulides, and M. Khajavikhan, Non-Hermitian ring laser gyroscopes with enhanced Sagnac sensitivity, Nature (London) 576, 70 (2019).
- Z. Xiao, H. Li, T. Kottos, and A. Alù, Enhanced sensing and nondegraded thermal noise performance based on -symmetric electronic circuits with a sixth-order exceptional point, Phys. Rev. Lett. 123, 213901 (2019).
- A. McDonald and A. A. Clerk, Exponentially-enhanced quantum sensing with non-Hermitian lattice dynamics, Nat. Commun. 11, 5382 (2020).
- J. Park, A. Ndao, W. Cai, L. Hsu, A. Kodigala, T. Lepetit, Y. Lo, and B. Kanté, Symmetry-breaking-induced plasmonic exceptional points and nanoscale sensing, Nat. Phys. 16, 462 (2020).
- R. Kononchuk, J. Cai, F. Ellis, R. Thevamaran, and T. Kottos, Exceptional-point-based accelerometers with enhanced signal-to-noise ratio, Nature (London) 607, 697 (2022).
- J. Doppler, A. A. Mailybaev, J. Böhm, U. Kuhl, A. Girschik, F. Libisch, T. J. Milburn, P. Rabl, N. Moiseyev, and S. Rotter, Dynamically encircling an exceptional point for asymmetric mode switching, Nature (London) 537, 76 (2016).
- X.-L. Zhang, T. Jiang, and C. T. Chan, Dynamically encircling an exceptional point in anti-parity-time symmetric systems: Asymmetric mode switching for symmetry-broken modes, Light Sci. Appl. 8, 88 (2019).
- A. Li, J. Dong, J. Wang, Z. Cheng, J. S. Ho, D. Zhang, J. Wen, X.-L. Zhang, C. T. Chan, A. Alù, C.-W. Qiu, and L. Chen, Hamiltonian hopping for efficient Chiral mode switching in encircling exceptional points, Phys. Rev. Lett. 125, 187403 (2020).
- X. Shu, A. Li, G. Hu, J. Wang, A. Alù, and L. Chen, Fast encirclement of an exceptional point for highly efficient and compact chiral mode converters, Nat. Commun. 13, 2123 (2022).
- A. Li, W. Chen, H. Wei, G. Lu, A. Alù, C.-W. Qiu, and L. Chen, Riemann-encircling exceptional points for efficient asymmetric polarization-locked devices, Phys. Rev. Lett. 129, 127401 (2022).
- Y. Chen, F. Zhang, T. Qin, G. Zhao, J. Hou, X. Chen, L. Ge, and W. Wan, Exceptional points with memory in a microcavity Brillouin laser, Optica 9, 971 (2022).
- Y. Zhang, W. Liu, S. Ren, T. Chai, Y. Wang, H. Long, K. Wang, B. Wang, and P. Lu, Asymmetric switching of edge modes by dynamically encircling multiple exceptional points, Phys. Rev. Appl. 19, 064050 (2023).
- K. Ding, G. Ma, M. Xiao, Z. Q. Zhang, and C. T. Chan, Emergence, coalescence, and topological properties of multiple exceptional points and their experimental realization, Phys. Rev. X 6, 021007 (2016).
- L. Jin, Parity-time-symmetric coupled asymmetric dimers, Phys. Rev. A 97, 012121 (2018).
- Q. Zhong, M. Khajavikhan, D. N. Christodoulides, and R. El-Ganainy, Winding around non-Hermitian singularities, Nat. Commun. 9, 4808 (2018).
- L. Jin, H. C. Wu, B.-B. Wei, and Z. Song, Hybrid exceptional point created from type-III Dirac point, Phys. Rev. B 101, 045130 (2020).
- G.-Q. Zhang, Z. Chen, D. Xu, N. Shammah, M. Liao, T.-F. Li, L. Tong, S.-Y. Zhu, F. Nori, and J. Q. You, Exceptional point and cross-relaxation effect in a hybrid quantum system, PRX Quantum 2, 020307 (2021).
- K. Wang, A. Dutt, C. C. Wojcik, and S. Fan, Topological complex-energy braiding of non-Hermitian bands, Nature (London) 598, 59 (2021).
- K. Ding, C. Fang, and G. Ma, Non-Hermitian topology and exceptional-point geometries, Nat. Rev. Phys. 4, 745 (2022).
- C. C. Wojcik, K. Wang, A. Dutt, J. Zhong, and S. Fan, Eigenvalue topology of non-Hermitian band structures in two and three dimensions, Phys. Rev. B 106, L161401 (2022).
- C.-X. Guo, S. Chen, K. Ding, and H. Hu, Exceptional non-Abelian topology in multiband non-Hermitian systems, Phys. Rev. Lett. 130, 157201 (2023).
- A. A. Zyablovsky, A. P. Vinogradov, A. A. Pukhov, A. V. Dorofeenko, and A. A. Lisyansky, symmetry in optics, Phys. Usp. 57, 1063 (2014).
- S. V. Suchkov, A. A. Sukhorukov, J. Huang, S. V. Dmitriev, C. Lee, and Y. S. Kivshar, Nonlinear switching and solitons in PT-symmetric photonic systems, Laser Photonics Rev. 10, 177 (2016).
- L. Feng, R. El-Ganainy, and L. Ge, Non-Hermitian photonics based on parity-time symmetry, Nature Photon 11, 752 (2017).
- Y. Huang, Y. Shen, C. Min, S. Fan, and G. Veronis, Unidirectional reflectionless light propagation at exceptional points, Nanophotonics 6, 977 (2017).
- R. El-Ganainy, K. G. Makris, M. Khajavikhan, Z. H. Musslimani, S. Rotter, and D. N. Christodoulides, Non-Hermitian physics and symmetry, Nat. Phys. 14, 11 (2018).
- H. Zhao and L. Feng, Parity-time symmetric photonics, Natl. Sci. Rev. 5, 183 (2018).
- D. Christodoulides and J. Yang, Parity-Time Symmetry and Its Applications (Springer, Berlin, 2018).
- Ş. K. Özdemir, S. Rotter, F. Nori, and L. Yang, Parity-time symmetry and exceptional points in photonics, Nat. Mater. 18, 783 (2019).
- M.-A. Miri and A. Alù, Exceptional points in optics and photonics, Science 363, eaar7709 (2019).
- A. Li, H. Wei, M. Cotrufo, W. Chen, S. Mann, X. Ni, B. Xu, J. Chen, J. Wang, S. Fan, C.-W. Qiu, A. Alù, and L. Chen, Exceptional points and non-Hermitian photonics at the nanoscale, Nat. Nanotechnol. 18, 706 (2023).
- Q. Wang and Y. D. Chong, Non-Hermitian photonic lattices: tutorial, J. Opt. Soc. Am. B 40, 1443 (2023).
- H. Ramezani, T. Kottos, R. El-Ganainy, and D. N. Christodoulides, Unidirectional nonlinear -symmetric optical structures, Phys. Rev. A 82, 043803 (2010).
- M. H. Teimourpour, R. El-Ganainy, A. Eisfeld, A. Szameit, and D. N. Christodoulides, Light transport in -invariant photonic structures with hidden symmetries, Phys. Rev. A 90, 053817 (2014).
- J. D. H. Rivero and L. Ge, Pseudochirality: A manifestation of Noether's theorem in non-Hermitian systems, Phys. Rev. Lett. 125, 083902 (2020).
- Z. Bian, L. Xiao, K. Wang, X. Zhan, F. A. Onanga, F. Ruzicka, W. Yi, Y. N. Joglekar, and P. Xue, Conserved quantities in parity-time symmetric systems, Phys. Rev. Res. 2, 022039(R) (2020).
- F. Ruzicka, K. S. Agarwal, and Y. N. Joglekar, Conserved quantities, exceptional points, and antilinear symmetries in non-Hermitian systems, J. Phys.: Conf. Ser. 2038, 012021 (2021).
- Q.-C. Wu, J.-L. Zhao, Y.-L. Fang, Y. Zhang, D.-X. Chen, C.-P. Yang, and F. Nori, Extension of Noether's theorem in -symmetry systems and its experimental demonstration in an optical setup, Sci. China Phys. Mech. Astron. 66, 240312 (2023).
- L. Jin and Z. Song, Hermitian dynamics in a class of pseudo-Hermitian networks, Phys. Rev. A 84, 042116 (2011).
- L. Jin, Unitary scattering protected by pseudo-Hermiticity, Chin. Phys. Lett. 39, 037302 (2022).
- Y. Choi, C. Hahn, J. W. Yoon, and S. H. Song, Observation of an anti--symmetric exceptional point and energy-difference conserving dynamics in electrical circuit resonators, Nat. Commun. 9, 2182 (2018).
- Y. D. Chong, L. Ge, and A. D. Stone, -symmetry breaking and laser-absorber modes in optical scattering systems, Phys. Rev. Lett. 106, 093902 (2011).
- L. Ge, Y. D. Chong, and A. D. Stone, Conservation relations and anisotropic transmission resonances in one-dimensional -symmetric photonic heterostructures, Phys. Rev. A 85, 023802 (2012).
- L. Ge, K. G. Makris, D. N. Christodoulides, and L. Feng, Scattering in - and -symmetric multimode waveguides: Generalized conservation laws and spontaneous symmetry breaking beyond one dimension, Phys. Rev. A 92, 062135 (2015).
- L. Jin, X. Z. Zhang, G. Zhang, and Z. Song, Reciprocal and unidirectional scattering of parity-time symmetric structures, Sci. Rep. 6, 20976 (2016).
- L. Jin and Z. Song, Symmetry-protected scattering in non-Hermitian linear systems, Chin. Phys. Lett. 38, 024202 (2021).
- L. Jin, Scattering properties of a parity-time-antisymmetric non-Hermitian system, Phys. Rev. A 98, 022117 (2018).
- H. S. Xu and L. Jin, Coupling-induced nonunitary and unitary scattering in anti--symmetric non-Hermitian systems, Phys. Rev. A 104, 012218 (2021).
- D. C. Brody, Biorthogonal quantum mechanics, J. Phys. A: Math. Theor. 47, 035305 (2014).
- Z. Zhao, C. Guo, and S. Fan, Connection of temporal coupled-mode-theory formalisms for a resonant optical system and its time-reversal conjugate, Phys. Rev. A 99, 033839 (2019).
- C. Guo and S. Fan, Reciprocity constraints on reflection, Phys. Rev. Lett. 128, 256101 (2022).
- P. Peng, W. Cao, C. Shen, W. Qu, J. Wen, L. Jiang, and Y. Xiao, Anti-parity-time symmetry with flying atoms, Nat. Phys. 12, 1139 (2016).
- Y. Jiang, Y. Mei, Y. Zuo, Y. Zhai, J. Li, J. Wen, and S. Du, Anti-parity-time symmetric optical four-wave mixing in cold atoms, Phys. Rev. Lett. 123, 193604 (2019).
- X.-W. Luo, C. Zhang, and S. Du, Quantum squeezing and sensing with pseudo-anti-parity-time symmetry, Phys. Rev. Lett. 128, 173602 (2022).
- F. Yang, Y.-C. Liu, and L. You, Anti- symmetry in dissipatively coupled optical systems, Phys. Rev. A 96, 053845 (2017).
- V. V. Konotop and D. A. Zezyulin, Odd-time reversal symmetry induced by an anti--symmetric medium, Phys. Rev. Lett. 120, 123902 (2018).
- S. Ke, D. Zhao, Q. Liu, S. Wu, B. Wang, and P. Lu, Optical imaginary directional couplers, J. Lightwave Technol. 36, 2510 (2018).
- S. Ke, D. Zhao, J. Liu, Q. Liu, Q. Liao, B. Wang, and P. Lu, Topological bound modes in anti-PT-symmetric optical waveguide arrays, Opt. Express 27, 13858 (2019).
- H. Qi, X. Hu, X. Wang, and Q. Gong, Encircling an exceptional point in a multiwaveguide anti-parity-time-symmetry system, Phys. Rev. A 103, 063520 (2021).
- Z. Feng and X. Sun, Harnessing dynamical encircling of an exceptional point in anti--symmetric integrated photonic systems, Phys. Rev. Lett. 129, 273601 (2022).
- W. Liu, Y. Zhang, Z. Deng, J. Ye, K. Wang, B. Wang, D. Gao, and P. Lu, On-chip chiral mode switching by encircling an exceptional point in an anti-parity-time symmetric system, Laser Photonics Rev. 16, 2100675 (2022).
- Z. Feng, X. Sun, Experimental observation of dissipatively coupled bound states in the continuum on an integrated photonic platform, Laser Photonics Rev. 17, 2200961 (2023).
- S. Ke, W. Wen, D. Zhao, and Y. Wang, Floquet engineering of the non-Hermitian skin effect in photonic waveguide arrays, Phys. Rev. A 107, 053508 (2023).
- S. Longhi, Non-Hermitian tight-binding network engineering, Phys. Rev. A 93, 022102 (2016).
- Y.-H. Lai, Y.-K. Lu, M.-G. Suh, Z. Yuan, and K. Vahala, Observation of the exceptional-point-enhanced Sagnac effect, Nature (London) 576, 65 (2019).
- M. De Carlo, F. D. Leonardis, L. Lamberti, and V. M. N. Passaro, High-sensitivity real-splitting anti-PT-symmetric microscale optical gyroscope, Opt. Lett. 44, 3956 (2019).
- H. Zhang, R. Huang, S.-D. Zhang, Y. Li, C.-W. Qiu, F. Nori, and H. Jing, Breaking Anti-PT symmetry by spinning a resonator, Nano Lett. 20, 7594 (2020).
- J. Zhang, Z. Feng, X. Sun, Realization of bound states in the continuum in Anti-PT-symmetric optical systems: A proposal and analysis, Laser Photonics Rev. 17, 2200079 (2023).
- C. Leefmans, A. Dutt, J. Williams, L. Yuan, M. Parto, F. Nori, S. Fan, and A. Marandi, Topological dissipation in a time-multiplexed photonic resonator network, Nat. Phys. 18, 442 (2022).
- M. Peng, H. Zhang, Q. Zhang, T.-X. Lu, I. M. Mirza, and H. Jing, Nonreciprocal slow or fast light in anti--symmetric optomechanics, Phys. Rev. A 107, 033507 (2023).
- L. Xie, L. Jin, Z. Song, Antihelical edge states in two-dimensional photonic topological metals, Sci. Bull. 68, 255 (2023).
- F. Zhang, Y. Feng, X. Chen, L. Ge, and W. Wan, Synthetic anti-PT symmetry in a single microcavity, Phys. Rev. Lett. 124, 053901 (2020).
- S. Park, D. Lee, K. Park, H. Shin, Y. Choi, and J. W. Yoon, Optical energy-difference conservation in a synthetic anti-PT-symmetric system, Phys. Rev. Lett. 127, 083601 (2021).
- A. Bergman, R. Duggan, K. Sharma, M. Tur, A. Zadok, and A. Alù, Observation of anti-parity-time-symmetry, phase transitions and exceptional points in an optical fibre, Nat. Commun. 12, 486 (2021).
- H. Li, A. Mekawy, and A. Alù, Gain-free parity-time symmetry for evanescent fields, Phys. Rev. Lett. 127, 014301 (2021).
- Z. Xiao and A. Alù, Tailoring exceptional points in a hybrid PT-symmetric and anti-PT-symmetric scattering system, Nanophotonics 10, 3723 (2021).
- C. H. Lee, S. Imhof, C. Berger, F. Bayer, J. Brehm, L. W. Molenkamp, T. Kiessling, and R. Thomale, Topolectrical Circuits, Commun. Phys. 1, 39 (2018).
- F. Qin, Y. Ma, R. Shen, and C. H. Lee, Universal competitive spectral scaling from the critical non-Hermitian skin effect, Phys. Rev. B 107, 155430 (2023).
- Y. Li, Y.-G. Peng, L. Han, M.-A. Miri, W. Li, M. Xiao, X.-F. Zhu, J. Zhao, A. Alù, S. Fan, and C.-W. Qiu, Anti-parity-time symmetry in diffusive systems, Science 364, 170 (2019).
- Y. Yang, Y.-P. Wang, J. W. Rao, Y. S. Gui, B. M. Yao, W. Lu, and C.-M. Hu, Unconventional Singularity in anti-parity-time symmetric cavity magnonics, Phys. Rev. Lett. 125, 147202 (2020).
- J. Zhao, Y. Liu, L. Wu, C.-K. Duan, Y.-X. Liu, and J. Du, Observation of anti--symmetry phase transition in the magnon-cavity-magnon coupled system, Phys. Rev. Appl. 13, 014053 (2020).
- J. M. P. Nair, D. Mukhopadhyay, and G. S. Agarwal, Ultralow threshold bistability and generation of long-lived mode in a dissipatively coupled nonlinear system: Application to magnonics, Phys. Rev. B 103, 224401 (2021).
- J. M. P. Nair, D. Mukhopadhyay, and G. S. Agarwal, Enhanced sensing of weak anharmonicities through coherences in dissipatively coupled anti-PT symmetric systems, Phys. Rev. Lett. 126, 180401 (2021).
- C. Zhao, Z. Yang, R. Peng, J. Yang, C. Li, and L. Zhou, Dissipative-coupling-induced transparency and high-order sidebands with Kerr nonlinearity in a cavity-magnonics system, Phys. Rev. Appl. 18, 044074 (2022).
- Y. Yang, X. Xie, Y. Li, Z. Zhang, Y. Peng, C. Wang, E. Li, Y. Li, H. Chen, and F. Gao, Radiative anti-parity-time plasmonics, Nat. Commun. 13, 7678 (2022).
- See Supplemental Material at http://link.aps.org/supplemental/10.1103/PhysRevResearch.5.L042005 provides the scattering coefficients of and at and an example of a three-port scattering system.
- H. A. Haus, Waves and Fields in Optoelectronics (Prentice-Hall, Englewood Cliffs, NJ, 1984).
- A. Krasnok, D. Baranov, H. Li, M. A. Miri, F. Monticone, and A. Alù, Anomalies in light scattering, Adv. Opt. Photon. 11, 892 (2019).