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[Crossref]
[PubMed]

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[Crossref]

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[Crossref]

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[Crossref]

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[Crossref]
[PubMed]

R. P. Guo, L. T. Wu, M. Yang, T. J. Guo, H. X. Cui, X. W. Cao, and J. Chen, “Nonreciprocal propagating electromagnetic modes without phase gradients,” Phys. Rev. A 91, 023808 (2015).

[Crossref]

W. Wang, L. Q. Wang, R. D. Xue, H. L. Chen, R. P. Guo, Y. Liu, and J. Chen, “Unidirectional excitation of radiative-loss-free surface plasmon polaritons in PT-symmetric systems,” Phys. Rev. Lett. 119, 077401 (2017).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, M. Kang, and J. Chen, “High-order exceptional points in non-Hermitian Moire lattices,” Front. Physics 14, 53603 (2019).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, W. Wang, L. Q. Wang, Z. X. Li, R. D. Xue, and J. Chen, “Parity-time symmetry in periodically curved optical waveguides,” Opt. Express 26, 027141 (2018).

[Crossref]

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[Crossref]

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[Crossref]

T. F. Li, T. J. Guo, H. X. Cui, M. Yang, M. Kang, Q. H. Guo, and J. Chen, “Guided modes in magneto-optical waveguides and the role in resonant transmission,” Opt. Express 21, 9563–9572 (2013).

[Crossref]
[PubMed]

W. Chen, S. K. Ozdemir, G. Zhao, J. Wiersig, and L. Yang, “Exceptional points enhanced sensing in an optical microcavity,” Nature 548, 192–196 (2017).

[Crossref]
[PubMed]

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, 108–113 (2013).

[Crossref]

W. Wan, Y. Chong, L. Ge, H. Noh, A. D. Stone, and H. Cao, “Time-reversed lasing and interferometric control of absorption,” Science 331, 889–892 (2011).

[Crossref]
[PubMed]

D. G. Baranov, A. Krasnok, T. Shegai, A. Alù, and Y. D. Chong, “Coherent perfect absorbers: linear control of light with light,” Nat. Rev. Mater. 2, 17064 (2017).

[Crossref]

X. Zhou and Y. D. Chong, “PT symmetry breaking and nonlinear optical isolation in coupled microcavities,” Opt. Express 24, 6916–6930 (2016).

[Crossref]
[PubMed]

R. El-Ganainy, K. G. Makris, M. Khajavikhan, Z. H. Musslimani, S. Rotter, and D. N. Christodoulides, “Non-Hermitian physics and PT symmetry,” Nat. Phys. 14, 11–19 (2018).

[Crossref]

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 548, 187–191 (2017).

[Crossref]
[PubMed]

F. Nazari, N. Bender, H. Ramezani, M. K. Moravvej-Farshi, D. N. Christodoulides, and T. Kottos, “Optical isolation via PT-symmetric nonlinear Fano resonances,” Opt. Express 22, 9574 (2014).

[Crossref]
[PubMed]

C. E. Rüter, K. G. Makris, R. El-Ganainy, D. N. Christodoulides, M. Segev, and D. Kip, “Observation of parity-time symmetry in optics,” Nat. Phys. 6, 192–195 (2010).

[Crossref]

A. Guo, G. J. Salamo, D. Duchesne, R. Morandotti, M. Volatier-Ravat, V. Aimez, G. A. Siviloglou, and D. N. Christodoulides, “Observation of PT-symmetry breaking in complex optical potentials,” Phys. Rev. Lett. 103, 093902 (2009).

[Crossref]

R. El-Ganainy, K. G. Makris, D. N. Christodoulides, and Z. H. Musslimani, “Theory of coupled optical PT-symmetric structures,” Opt. Lett. 32, 2632–2634 (2007).

[Crossref]
[PubMed]

J. Gear, F. Liu, S. T. Chu, S. Rotter, and J. Li, “Parity-time symmetry from stacking purely dielectric and magnetic slabs,” Phys. Rev. A 91, 033825 (2015).

[Crossref]

M. Lawrence, N. Xu, X. Zhang, L. Cong, J. Han, W. Zhang, and S. Zhang, “Manifestation of PT symmetry breaking in polarization space with terahertz metasurfaces,” Phys. Rev. Lett. 113, 093901 (2014).

[Crossref]

R. P. Guo, L. T. Wu, M. Yang, T. J. Guo, H. X. Cui, X. W. Cao, and J. Chen, “Nonreciprocal propagating electromagnetic modes without phase gradients,” Phys. Rev. A 91, 023808 (2015).

[Crossref]

T. F. Li, T. J. Guo, H. X. Cui, M. Yang, M. Kang, Q. H. Guo, and J. Chen, “Guided modes in magneto-optical waveguides and the role in resonant transmission,” Opt. Express 21, 9563–9572 (2013).

[Crossref]
[PubMed]

A. A. Zyablovsky, A. P. Vinogradov, A. V. Dorofeenko, A. A. Pukhov, and A. A. Lisyansky, “Causality and phase transitions in PT-symmetric optical systems,” Phys. Rev. A 89, 033808 (2014).

[Crossref]

A. Guo, G. J. Salamo, D. Duchesne, R. Morandotti, M. Volatier-Ravat, V. Aimez, G. A. Siviloglou, and D. N. Christodoulides, “Observation of PT-symmetry breaking in complex optical potentials,” Phys. Rev. Lett. 103, 093902 (2009).

[Crossref]

B. Edwards, A. Alù, M. E. Young, M. Silveirinha, and N. Engheta, “Experimental verification of epsilon-near-zero metamaterial coupling and energy squeezing using a microwave waveguide,” Phys. Rev. Lett. 100, 033903 (2008).

[Crossref]
[PubMed]

R. El-Ganainy, K. G. Makris, M. Khajavikhan, Z. H. Musslimani, S. Rotter, and D. N. Christodoulides, “Non-Hermitian physics and PT symmetry,” Nat. Phys. 14, 11–19 (2018).

[Crossref]

L. Feng, R. El-Ganainy, and L. Ge, “Non-Hermitian photonics based on parity-time symmetry,” Nat. Photo. 11, 752–762 (2017).

[Crossref]

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 548, 187–191 (2017).

[Crossref]
[PubMed]

L. Ge and R. El-Ganainy, “Nonlinear modal interactions in parity-time (PT) symmetric lasers,” Sci. Rep. 6, 24889 (2016).

[Crossref]

C. E. Rüter, K. G. Makris, R. El-Ganainy, D. N. Christodoulides, M. Segev, and D. Kip, “Observation of parity-time symmetry in optics,” Nat. Phys. 6, 192–195 (2010).

[Crossref]

R. El-Ganainy, K. G. Makris, D. N. Christodoulides, and Z. H. Musslimani, “Theory of coupled optical PT-symmetric structures,” Opt. Lett. 32, 2632–2634 (2007).

[Crossref]
[PubMed]

R. Thomas, H. Li, F. M. Ellis, and T. Kottos, “Giant nonreciprocity near exceptional-point degeneracies,” Phys. Rev. A 94, 043829 (2016).

[Crossref]

I. Liberal and N. Engheta, "Near-zero refractive index photonics,” Nat. Photo. 11, 149–158 (2017).

[Crossref]

B. Edwards, A. Alù, M. E. Young, M. Silveirinha, and N. Engheta, “Experimental verification of epsilon-near-zero metamaterial coupling and energy squeezing using a microwave waveguide,” Phys. Rev. Lett. 100, 033903 (2008).

[Crossref]
[PubMed]

A. Y. Song, Y. Shi, Q. Lin, and S. Fan, “Direction-dependent parity-time phase transition and nonreciprocal amplification with dynamic gain-loss modulation,” Phys. Rev. A 99, 013824 (2019).

[Crossref]

S. Assawaworrarit, X. Yu, and S. Fan, “Robust wireless power transfer using a nonlinear parity-time-symmetric circuit,” Nature 546, 387–390 (2017).

[Crossref]
[PubMed]

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, 108–113 (2013).

[Crossref]

L. Feng, R. El-Ganainy, and L. Ge, “Non-Hermitian photonics based on parity-time symmetry,” Nat. Photo. 11, 752–762 (2017).

[Crossref]

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, 108–113 (2013).

[Crossref]

S. A. H. Gangaraj and F. Monticone, “Topological waveguiding near an exceptional point: defect-immune, slow-light, and loss-immune propagation,” Phys. Rev. Lett. 121, 093901 (2018).

[Crossref]

S. A. H. Gangaraj and F. Monticone, “Coupled topological surface modes in gyrotropic structures: Green’s function analysis,” IEEE Ant. Wireless Propag. Lett. 17, 1993–1997 (2018).

[Crossref]

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 548, 187–191 (2017).

[Crossref]
[PubMed]

L. Feng, R. El-Ganainy, and L. Ge, “Non-Hermitian photonics based on parity-time symmetry,” Nat. Photo. 11, 752–762 (2017).

[Crossref]

L. Ge and R. El-Ganainy, “Nonlinear modal interactions in parity-time (PT) symmetric lasers,” Sci. Rep. 6, 24889 (2016).

[Crossref]

W. Wan, Y. Chong, L. Ge, H. Noh, A. D. Stone, and H. Cao, “Time-reversed lasing and interferometric control of absorption,” Science 331, 889–892 (2011).

[Crossref]
[PubMed]

J. Gear, F. Liu, S. T. Chu, S. Rotter, and J. Li, “Parity-time symmetry from stacking purely dielectric and magnetic slabs,” Phys. Rev. A 91, 033825 (2015).

[Crossref]

T. Goldzak, A. A. Mailybaev, and N. Moiseyev, “Light stops at exceptional points,” Phys. Rev. Lett. 120, 013901 (2018).

[Crossref]
[PubMed]

S. Klaiman, U. Gunther, and N. Moiseyev, “Visualization of branch points in PT-symmetric waveguides,” Phys. Rev. Lett. 101, 080402 (2008).

[Crossref]

A. Guo, G. J. Salamo, D. Duchesne, R. Morandotti, M. Volatier-Ravat, V. Aimez, G. A. Siviloglou, and D. N. Christodoulides, “Observation of PT-symmetry breaking in complex optical potentials,” Phys. Rev. Lett. 103, 093902 (2009).

[Crossref]

W. Wang, L. Q. Wang, R. D. Xue, H. L. Chen, R. P. Guo, Y. Liu, and J. Chen, “Unidirectional excitation of radiative-loss-free surface plasmon polaritons in PT-symmetric systems,” Phys. Rev. Lett. 119, 077401 (2017).

[Crossref]

R. P. Guo, L. T. Wu, M. Yang, T. J. Guo, H. X. Cui, X. W. Cao, and J. Chen, “Nonreciprocal propagating electromagnetic modes without phase gradients,” Phys. Rev. A 91, 023808 (2015).

[Crossref]

R. P. Guo, L. T. Wu, M. Yang, T. J. Guo, H. X. Cui, X. W. Cao, and J. Chen, “Nonreciprocal propagating electromagnetic modes without phase gradients,” Phys. Rev. A 91, 023808 (2015).

[Crossref]

T. F. Li, T. J. Guo, H. X. Cui, M. Yang, M. Kang, Q. H. Guo, and J. Chen, “Guided modes in magneto-optical waveguides and the role in resonant transmission,” Opt. Express 21, 9563–9572 (2013).

[Crossref]
[PubMed]

M. Lawrence, N. Xu, X. Zhang, L. Cong, J. Han, W. Zhang, and S. Zhang, “Manifestation of PT symmetry breaking in polarization space with terahertz metasurfaces,” Phys. Rev. Lett. 113, 093901 (2014).

[Crossref]

A. B. Yakovlev and G. W. Hanson, “Fundamental modal phenomena on isotropic and anisotropic planar slab dielectric waveguides,” IEEE Trans. Antennas Propag. 51, 888–897 (2003).

[Crossref]

G. W. Hanson and A. B. Yakovlev, “Investigation of mode interaction on planar dielectric waveguides with loss and gain,” Radio Sci. 34, 1349–1359 (1999).

[Crossref]

G. W. Hanson and A. B. Yakovlev, “An analysis of leaky wave dispersion phenomena in the vicinity of cutoff using complex frequency plane singularities,” Radio Sci. 33, 803–819 (1998).

[Crossref]

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 548, 187–191 (2017).

[Crossref]
[PubMed]

W. D. Heiss, “Chirality of wavefunctions for three coalescing levels,” J. Phys. A 41, 244010 (2008).

[Crossref]

A. Pick, B. Zhen, O. D. Miller, C. W. Hsu, F. Hernandez, A. W. Rodriguez, M. Soljacic, and S. G. Johnson, “General theory of spontaneous emission near exceptional points,” Opt. Express 25, 012325 (2017).

[Crossref]

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 548, 187–191 (2017).

[Crossref]
[PubMed]

A. Pick, B. Zhen, O. D. Miller, C. W. Hsu, F. Hernandez, A. W. Rodriguez, M. Soljacic, and S. G. Johnson, “General theory of spontaneous emission near exceptional points,” Opt. Express 25, 012325 (2017).

[Crossref]

A. Pick, B. Zhen, O. D. Miller, C. W. Hsu, F. Hernandez, A. W. Rodriguez, M. Soljacic, and S. G. Johnson, “General theory of spontaneous emission near exceptional points,” Opt. Express 25, 012325 (2017).

[Crossref]

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T. F. Li, T. J. Guo, H. X. Cui, M. Yang, M. Kang, Q. H. Guo, and J. Chen, “Guided modes in magneto-optical waveguides and the role in resonant transmission,” Opt. Express 21, 9563–9572 (2013).

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S. Klaiman, U. Gunther, and N. Moiseyev, “Visualization of branch points in PT-symmetric waveguides,” Phys. Rev. Lett. 101, 080402 (2008).

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V. V. Konotop, J. Yang, and D. A. Zezyulin, “Nonlinear waves in PT-symmetric systems,” Rev. Mod. Phys. 88, 035002 (2016).

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R. Thomas, H. Li, F. M. Ellis, and T. Kottos, “Giant nonreciprocity near exceptional-point degeneracies,” Phys. Rev. A 94, 043829 (2016).

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[Crossref]
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[Crossref]

M. Lawrence, N. Xu, X. Zhang, L. Cong, J. Han, W. Zhang, and S. Zhang, “Manifestation of PT symmetry breaking in polarization space with terahertz metasurfaces,” Phys. Rev. Lett. 113, 093901 (2014).

[Crossref]

R. Thomas, H. Li, F. M. Ellis, and T. Kottos, “Giant nonreciprocity near exceptional-point degeneracies,” Phys. Rev. A 94, 043829 (2016).

[Crossref]

J. Gear, F. Liu, S. T. Chu, S. Rotter, and J. Li, “Parity-time symmetry from stacking purely dielectric and magnetic slabs,” Phys. Rev. A 91, 033825 (2015).

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Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, W. Wang, L. Q. Wang, Z. X. Li, R. D. Xue, and J. Chen, “Parity-time symmetry in periodically curved optical waveguides,” Opt. Express 26, 027141 (2018).

[Crossref]

I. Liberal and N. Engheta, "Near-zero refractive index photonics,” Nat. Photo. 11, 149–158 (2017).

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A. Y. Song, Y. Shi, Q. Lin, and S. Fan, “Direction-dependent parity-time phase transition and nonreciprocal amplification with dynamic gain-loss modulation,” Phys. Rev. A 99, 013824 (2019).

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Z. Lin, A. Pick, M. Loncar, and A. W. Rodriguez, “Enhanced spontaneous emission at third-order Dirac exceptional points in inverse-designed photonic crystals,” Phys. Rev. Lett. 117, 107402 (2016).

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[PubMed]

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[Crossref]

C. E. Rüter, K. G. Makris, R. El-Ganainy, D. N. Christodoulides, M. Segev, and D. Kip, “Observation of parity-time symmetry in optics,” Nat. Phys. 6, 192–195 (2010).

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R. El-Ganainy, K. G. Makris, D. N. Christodoulides, and Z. H. Musslimani, “Theory of coupled optical PT-symmetric structures,” Opt. Lett. 32, 2632–2634 (2007).

[Crossref]
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[Crossref]
[PubMed]

T. Goldzak, A. A. Mailybaev, and N. Moiseyev, “Light stops at exceptional points,” Phys. Rev. Lett. 120, 013901 (2018).

[Crossref]
[PubMed]

S. Klaiman, U. Gunther, and N. Moiseyev, “Visualization of branch points in PT-symmetric waveguides,” Phys. Rev. Lett. 101, 080402 (2008).

[Crossref]

S. A. H. Gangaraj and F. Monticone, “Topological waveguiding near an exceptional point: defect-immune, slow-light, and loss-immune propagation,” Phys. Rev. Lett. 121, 093901 (2018).

[Crossref]

S. A. H. Gangaraj and F. Monticone, “Coupled topological surface modes in gyrotropic structures: Green’s function analysis,” IEEE Ant. Wireless Propag. Lett. 17, 1993–1997 (2018).

[Crossref]

A. Guo, G. J. Salamo, D. Duchesne, R. Morandotti, M. Volatier-Ravat, V. Aimez, G. A. Siviloglou, and D. N. Christodoulides, “Observation of PT-symmetry breaking in complex optical potentials,” Phys. Rev. Lett. 103, 093902 (2009).

[Crossref]

R. El-Ganainy, K. G. Makris, M. Khajavikhan, Z. H. Musslimani, S. Rotter, and D. N. Christodoulides, “Non-Hermitian physics and PT symmetry,” Nat. Phys. 14, 11–19 (2018).

[Crossref]

R. El-Ganainy, K. G. Makris, D. N. Christodoulides, and Z. H. Musslimani, “Theory of coupled optical PT-symmetric structures,” Opt. Lett. 32, 2632–2634 (2007).

[Crossref]
[PubMed]

W. Wan, Y. Chong, L. Ge, H. Noh, A. D. Stone, and H. Cao, “Time-reversed lasing and interferometric control of absorption,” Science 331, 889–892 (2011).

[Crossref]
[PubMed]

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, 108–113 (2013).

[Crossref]

W. Chen, S. K. Ozdemir, G. Zhao, J. Wiersig, and L. Yang, “Exceptional points enhanced sensing in an optical microcavity,” Nature 548, 192–196 (2017).

[Crossref]
[PubMed]

A. Pick, B. Zhen, O. D. Miller, C. W. Hsu, F. Hernandez, A. W. Rodriguez, M. Soljacic, and S. G. Johnson, “General theory of spontaneous emission near exceptional points,” Opt. Express 25, 012325 (2017).

[Crossref]

Z. Lin, A. Pick, M. Loncar, and A. W. Rodriguez, “Enhanced spontaneous emission at third-order Dirac exceptional points in inverse-designed photonic crystals,” Phys. Rev. Lett. 117, 107402 (2016).

[Crossref]
[PubMed]

Y. Lumer, Y. Plotnik, M. C. Rechtsman, and M. Segev, “Nonlinearly induced PT transition in photonic systems,” Phys. Rev. Lett. 111, 263901 (2013).

[Crossref]

A. A. Zyablovsky, A. P. Vinogradov, A. V. Dorofeenko, A. A. Pukhov, and A. A. Lisyansky, “Causality and phase transitions in PT-symmetric optical systems,” Phys. Rev. A 89, 033808 (2014).

[Crossref]

Y. Lumer, Y. Plotnik, M. C. Rechtsman, and M. Segev, “Nonlinearly induced PT transition in photonic systems,” Phys. Rev. Lett. 111, 263901 (2013).

[Crossref]

A. Pick, B. Zhen, O. D. Miller, C. W. Hsu, F. Hernandez, A. W. Rodriguez, M. Soljacic, and S. G. Johnson, “General theory of spontaneous emission near exceptional points,” Opt. Express 25, 012325 (2017).

[Crossref]

Z. Lin, A. Pick, M. Loncar, and A. W. Rodriguez, “Enhanced spontaneous emission at third-order Dirac exceptional points in inverse-designed photonic crystals,” Phys. Rev. Lett. 117, 107402 (2016).

[Crossref]
[PubMed]

R. El-Ganainy, K. G. Makris, M. Khajavikhan, Z. H. Musslimani, S. Rotter, and D. N. Christodoulides, “Non-Hermitian physics and PT symmetry,” Nat. Phys. 14, 11–19 (2018).

[Crossref]

J. Gear, F. Liu, S. T. Chu, S. Rotter, and J. Li, “Parity-time symmetry from stacking purely dielectric and magnetic slabs,” Phys. Rev. A 91, 033825 (2015).

[Crossref]

C. E. Rüter, K. G. Makris, R. El-Ganainy, D. N. Christodoulides, M. Segev, and D. Kip, “Observation of parity-time symmetry in optics,” Nat. Phys. 6, 192–195 (2010).

[Crossref]

A. Guo, G. J. Salamo, D. Duchesne, R. Morandotti, M. Volatier-Ravat, V. Aimez, G. A. Siviloglou, and D. N. Christodoulides, “Observation of PT-symmetry breaking in complex optical potentials,” Phys. Rev. Lett. 103, 093902 (2009).

[Crossref]

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, 108–113 (2013).

[Crossref]

Y. Lumer, Y. Plotnik, M. C. Rechtsman, and M. Segev, “Nonlinearly induced PT transition in photonic systems,” Phys. Rev. Lett. 111, 263901 (2013).

[Crossref]

C. E. Rüter, K. G. Makris, R. El-Ganainy, D. N. Christodoulides, M. Segev, and D. Kip, “Observation of parity-time symmetry in optics,” Nat. Phys. 6, 192–195 (2010).

[Crossref]

D. G. Baranov, A. Krasnok, T. Shegai, A. Alù, and Y. D. Chong, “Coherent perfect absorbers: linear control of light with light,” Nat. Rev. Mater. 2, 17064 (2017).

[Crossref]

A. Y. Song, Y. Shi, Q. Lin, and S. Fan, “Direction-dependent parity-time phase transition and nonreciprocal amplification with dynamic gain-loss modulation,” Phys. Rev. A 99, 013824 (2019).

[Crossref]

B. Edwards, A. Alù, M. E. Young, M. Silveirinha, and N. Engheta, “Experimental verification of epsilon-near-zero metamaterial coupling and energy squeezing using a microwave waveguide,” Phys. Rev. Lett. 100, 033903 (2008).

[Crossref]
[PubMed]

A. Guo, G. J. Salamo, D. Duchesne, R. Morandotti, M. Volatier-Ravat, V. Aimez, G. A. Siviloglou, and D. N. Christodoulides, “Observation of PT-symmetry breaking in complex optical potentials,” Phys. Rev. Lett. 103, 093902 (2009).

[Crossref]

A. Pick, B. Zhen, O. D. Miller, C. W. Hsu, F. Hernandez, A. W. Rodriguez, M. Soljacic, and S. G. Johnson, “General theory of spontaneous emission near exceptional points,” Opt. Express 25, 012325 (2017).

[Crossref]

A. Y. Song, Y. Shi, Q. Lin, and S. Fan, “Direction-dependent parity-time phase transition and nonreciprocal amplification with dynamic gain-loss modulation,” Phys. Rev. A 99, 013824 (2019).

[Crossref]

W. Wan, Y. Chong, L. Ge, H. Noh, A. D. Stone, and H. Cao, “Time-reversed lasing and interferometric control of absorption,” Science 331, 889–892 (2011).

[Crossref]
[PubMed]

R. Thomas, H. Li, F. M. Ellis, and T. Kottos, “Giant nonreciprocity near exceptional-point degeneracies,” Phys. Rev. A 94, 043829 (2016).

[Crossref]

A. A. Zyablovsky, A. P. Vinogradov, A. V. Dorofeenko, A. A. Pukhov, and A. A. Lisyansky, “Causality and phase transitions in PT-symmetric optical systems,” Phys. Rev. A 89, 033808 (2014).

[Crossref]

A. Guo, G. J. Salamo, D. Duchesne, R. Morandotti, M. Volatier-Ravat, V. Aimez, G. A. Siviloglou, and D. N. Christodoulides, “Observation of PT-symmetry breaking in complex optical potentials,” Phys. Rev. Lett. 103, 093902 (2009).

[Crossref]

W. Wan, Y. Chong, L. Ge, H. Noh, A. D. Stone, and H. Cao, “Time-reversed lasing and interferometric control of absorption,” Science 331, 889–892 (2011).

[Crossref]
[PubMed]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, W. Wang, L. Q. Wang, Z. X. Li, R. D. Xue, and J. Chen, “Parity-time symmetry in periodically curved optical waveguides,” Opt. Express 26, 027141 (2018).

[Crossref]

W. Wang, L. Q. Wang, R. D. Xue, H. L. Chen, R. P. Guo, Y. Liu, and J. Chen, “Unidirectional excitation of radiative-loss-free surface plasmon polaritons in PT-symmetric systems,” Phys. Rev. Lett. 119, 077401 (2017).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, W. Wang, L. Q. Wang, Z. X. Li, R. D. Xue, and J. Chen, “Parity-time symmetry in periodically curved optical waveguides,” Opt. Express 26, 027141 (2018).

[Crossref]

W. Wang, L. Q. Wang, R. D. Xue, H. L. Chen, R. P. Guo, Y. Liu, and J. Chen, “Unidirectional excitation of radiative-loss-free surface plasmon polaritons in PT-symmetric systems,” Phys. Rev. Lett. 119, 077401 (2017).

[Crossref]

W. Chen, S. K. Ozdemir, G. Zhao, J. Wiersig, and L. Yang, “Exceptional points enhanced sensing in an optical microcavity,” Nature 548, 192–196 (2017).

[Crossref]
[PubMed]

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[Crossref]

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 548, 187–191 (2017).

[Crossref]
[PubMed]

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[Crossref]

M. Lawrence, N. Xu, X. Zhang, L. Cong, J. Han, W. Zhang, and S. Zhang, “Manifestation of PT symmetry breaking in polarization space with terahertz metasurfaces,” Phys. Rev. Lett. 113, 093901 (2014).

[Crossref]

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, 108–113 (2013).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, W. Wang, L. Q. Wang, Z. X. Li, R. D. Xue, and J. Chen, “Parity-time symmetry in periodically curved optical waveguides,” Opt. Express 26, 027141 (2018).

[Crossref]

W. Wang, L. Q. Wang, R. D. Xue, H. L. Chen, R. P. Guo, Y. Liu, and J. Chen, “Unidirectional excitation of radiative-loss-free surface plasmon polaritons in PT-symmetric systems,” Phys. Rev. Lett. 119, 077401 (2017).

[Crossref]

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[Crossref]

V. V. Konotop, J. Yang, and D. A. Zezyulin, “Nonlinear waves in PT-symmetric systems,” Rev. Mod. Phys. 88, 035002 (2016).

[Crossref]

W. Chen, S. K. Ozdemir, G. Zhao, J. Wiersig, and L. Yang, “Exceptional points enhanced sensing in an optical microcavity,” Nature 548, 192–196 (2017).

[Crossref]
[PubMed]

R. P. Guo, L. T. Wu, M. Yang, T. J. Guo, H. X. Cui, X. W. Cao, and J. Chen, “Nonreciprocal propagating electromagnetic modes without phase gradients,” Phys. Rev. A 91, 023808 (2015).

[Crossref]

T. F. Li, T. J. Guo, H. X. Cui, M. Yang, M. Kang, Q. H. Guo, and J. Chen, “Guided modes in magneto-optical waveguides and the role in resonant transmission,” Opt. Express 21, 9563–9572 (2013).

[Crossref]
[PubMed]

B. Edwards, A. Alù, M. E. Young, M. Silveirinha, and N. Engheta, “Experimental verification of epsilon-near-zero metamaterial coupling and energy squeezing using a microwave waveguide,” Phys. Rev. Lett. 100, 033903 (2008).

[Crossref]
[PubMed]

S. Assawaworrarit, X. Yu, and S. Fan, “Robust wireless power transfer using a nonlinear parity-time-symmetric circuit,” Nature 546, 387–390 (2017).

[Crossref]
[PubMed]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, M. Kang, and J. Chen, “High-order exceptional points in non-Hermitian Moire lattices,” Front. Physics 14, 53603 (2019).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, W. Wang, L. Q. Wang, Z. X. Li, R. D. Xue, and J. Chen, “Parity-time symmetry in periodically curved optical waveguides,” Opt. Express 26, 027141 (2018).

[Crossref]

V. V. Konotop, J. Yang, and D. A. Zezyulin, “Nonlinear waves in PT-symmetric systems,” Rev. Mod. Phys. 88, 035002 (2016).

[Crossref]

M. Lawrence, N. Xu, X. Zhang, L. Cong, J. Han, W. Zhang, and S. Zhang, “Manifestation of PT symmetry breaking in polarization space with terahertz metasurfaces,” Phys. Rev. Lett. 113, 093901 (2014).

[Crossref]

M. Lawrence, N. Xu, X. Zhang, L. Cong, J. Han, W. Zhang, and S. Zhang, “Manifestation of PT symmetry breaking in polarization space with terahertz metasurfaces,” Phys. Rev. Lett. 113, 093901 (2014).

[Crossref]

M. Lawrence, N. Xu, X. Zhang, L. Cong, J. Han, W. Zhang, and S. Zhang, “Manifestation of PT symmetry breaking in polarization space with terahertz metasurfaces,” Phys. Rev. Lett. 113, 093901 (2014).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, M. Kang, and J. Chen, “High-order exceptional points in non-Hermitian Moire lattices,” Front. Physics 14, 53603 (2019).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, W. Wang, L. Q. Wang, Z. X. Li, R. D. Xue, and J. Chen, “Parity-time symmetry in periodically curved optical waveguides,” Opt. Express 26, 027141 (2018).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, M. Kang, and J. Chen, “High-order exceptional points in non-Hermitian Moire lattices,” Front. Physics 14, 53603 (2019).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, W. Wang, L. Q. Wang, Z. X. Li, R. D. Xue, and J. Chen, “Parity-time symmetry in periodically curved optical waveguides,” Opt. Express 26, 027141 (2018).

[Crossref]

W. Chen, S. K. Ozdemir, G. Zhao, J. Wiersig, and L. Yang, “Exceptional points enhanced sensing in an optical microcavity,” Nature 548, 192–196 (2017).

[Crossref]
[PubMed]

A. Pick, B. Zhen, O. D. Miller, C. W. Hsu, F. Hernandez, A. W. Rodriguez, M. Soljacic, and S. G. Johnson, “General theory of spontaneous emission near exceptional points,” Opt. Express 25, 012325 (2017).

[Crossref]

A. A. Zyablovsky, A. P. Vinogradov, A. V. Dorofeenko, A. A. Pukhov, and A. A. Lisyansky, “Causality and phase transitions in PT-symmetric optical systems,” Phys. Rev. A 89, 033808 (2014).

[Crossref]

Y. R. Zhang, Z. Z. Zhang, J. Q. Yuan, M. Kang, and J. Chen, “High-order exceptional points in non-Hermitian Moire lattices,” Front. Physics 14, 53603 (2019).

[Crossref]

S. A. H. Gangaraj and F. Monticone, “Coupled topological surface modes in gyrotropic structures: Green’s function analysis,” IEEE Ant. Wireless Propag. Lett. 17, 1993–1997 (2018).

[Crossref]

A. B. Yakovlev and G. W. Hanson, “Fundamental modal phenomena on isotropic and anisotropic planar slab dielectric waveguides,” IEEE Trans. Antennas Propag. 51, 888–897 (2003).

[Crossref]

W. D. Heiss, “Chirality of wavefunctions for three coalescing levels,” J. Phys. A 41, 244010 (2008).

[Crossref]

S. Longhi, “Quantum-optical analogies using photonic structures,” Laser Photon. Rev. 3, 243–261 (2009).

[Crossref]

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, 108–113 (2013).

[Crossref]

J. B. Khurgin, “How to deal with the loss in plasmonics and metamaterials,” Nat. Nanotech. 10, 2–6 (2015).

[Crossref]

L. Feng, R. El-Ganainy, and L. Ge, “Non-Hermitian photonics based on parity-time symmetry,” Nat. Photo. 11, 752–762 (2017).

[Crossref]

I. Liberal and N. Engheta, "Near-zero refractive index photonics,” Nat. Photo. 11, 149–158 (2017).

[Crossref]

R. El-Ganainy, K. G. Makris, M. Khajavikhan, Z. H. Musslimani, S. Rotter, and D. N. Christodoulides, “Non-Hermitian physics and PT symmetry,” Nat. Phys. 14, 11–19 (2018).

[Crossref]

C. E. Rüter, K. G. Makris, R. El-Ganainy, D. N. Christodoulides, M. Segev, and D. Kip, “Observation of parity-time symmetry in optics,” Nat. Phys. 6, 192–195 (2010).

[Crossref]

D. G. Baranov, A. Krasnok, T. Shegai, A. Alù, and Y. D. Chong, “Coherent perfect absorbers: linear control of light with light,” Nat. Rev. Mater. 2, 17064 (2017).

[Crossref]

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 548, 187–191 (2017).

[Crossref]
[PubMed]

W. Chen, S. K. Ozdemir, G. Zhao, J. Wiersig, and L. Yang, “Exceptional points enhanced sensing in an optical microcavity,” Nature 548, 192–196 (2017).

[Crossref]
[PubMed]

S. Assawaworrarit, X. Yu, and S. Fan, “Robust wireless power transfer using a nonlinear parity-time-symmetric circuit,” Nature 546, 387–390 (2017).

[Crossref]
[PubMed]

X. Zhou and Y. D. Chong, “PT symmetry breaking and nonlinear optical isolation in coupled microcavities,” Opt. Express 24, 6916–6930 (2016).

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