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

[Crossref]

L. Ge and L. Feng, “Contrasting eigenvalue and singular-value spectra for lasing and antilasing in a PT-symmetric periodic structure,” Phys. Rev. A 95, 013813 (2017).

[Crossref]

V. Achilleos, G. Theocharis, O. Richoux, and V. Pagneux, “Non-hermitian acoustic metamaterials: Role of exceptional points in sound absorption,” Phys. Rev. B 95, 144303 (2017).

[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]
[PubMed]

G. C. R. Devarapu and S. Foteinopoulou, “Broadband near-unidirectional absorption enabled by phonon-polariton resonances in SiC micropyramid arrays,” Phys. Rev. Applied 7, 034001 (2017).

[Crossref]

H. Zhao, W. Fegadolli, J. Yu, Z. Zhang, L. Ge, A. Scherer, and L. Feng, “Metawaveguide for asymmetric interferometric light-light switching,” Phys. Rev. Lett. 117, 193901 (2016).

[Crossref]
[PubMed]

L. Ge and L. Feng, “Optical-reciprocity-induced symmetry in photonic heterostructures and its manifestation in scattering PT-symmetry breaking,” Phys. Rev. A 94, 043836 (2016).

[Crossref]

Z. J. Wong, Y.-L. Xu, J. Kim, K. O’Brien, Y. Wang, L. Feng, and X. Zhang, “Lasing and anti-lasing in a single cavity,” Nature Photonics 10, 796 (2016).

[Crossref]

J.-H. Wu, M. Artoni, and G. C. La Rocca, “Coherent perfect absorption in one-sided reflectionless media,” Scientific Reports 6, 35356 (2016).

[Crossref]
[PubMed]

L. Ge, K. G. Makris, D. N. Christodoulides, and L. Feng, “Scattering in PT- and RT-symmetric multimode waveguides: Generalized conservation laws and spontaneous symmetry breaking,” Phys. Rev. A 92, 062135 (2015).

[Crossref]

L. Baldacci, S. Zanotto, G. Biasiol, L. Sorba, and A. Tredicucci, “Interferometric control of absorption in thin plasmonic metamaterials: general two port theory and broadband operation,” Opt. Express 23, 9202 (2015).

[Crossref]
[PubMed]

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,” Nature Communications 6, 7031 (2015).

[Crossref]
[PubMed]

J.-H. Wu, M. Artoni, and G. C. La Rocca, “Non-hermitian degeneracies and unidirectional reflectionless atomic lattices,” Phys. Rev. Lett. 113, 123004 (2014).

[Crossref]
[PubMed]

S. Huang and G. S. Agarwal, “Coherent perfect absorption of path entangled single photons,” Opt. Express 22, 20936 (2014).

[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]
[PubMed]

P. Ambichl, K. G. Makris, L. Ge, Y. Chong, A. D. Stone, and S. Rotter, “Breaking of PT symmetry in bounded and unbounded scattering systems,” Phys. Rev. X 3, 041030 (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,” Nature Materials 12, 108 (2012).

[Crossref]
[PubMed]

A. Regensburger, C. Bersch, M.-A. Miri, G. Onishchukov, D. N. Christodoulides, and U. Peschel, “Parity-time synthetic photonic lattices,” Nature 488, 167 (2012).

[Crossref]
[PubMed]

Z. Lin, H. Ramezani, T. Eichelkraut, T. Kottos, H. Cao, and D. N. Christodoulides, “Unidirectional invisibility induced by PT-symmetric periodic structures,” Phys. Rev. Lett. 106, 213901 (2011).

[Crossref]
[PubMed]

Y. D. Chong, L. Ge, and A. D. Stone, “PT-symmetry breaking and laser-absorber modes in optical scattering systems,” Phys. Rev. Lett. 106, 093902 (2011).

[Crossref]
[PubMed]

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

[Crossref]
[PubMed]

Y. D. Chong, L. Ge, H. Cao, and A. D. Stone, “Coherent perfect absorbers: Time-reversed lasers,” Phys. Rev. Lett. 105, 053901 (2010).

[Crossref]
[PubMed]

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[Crossref]
[PubMed]

S. Longhi, “PT-symmetric laser absorber,” Phys. Rev. A 82, 031801 (2010).

[Crossref]

S. Xiao, V. P. Drachev, A. V. Kildishev, X. Ni, U. K. Chettiar, H.-K. Yuan, and V. M. Shalaev, “Loss-free and active optical negative-index metamaterials,” Nature 466, 735 (2010).

[Crossref]
[PubMed]

S. Wuestner, A. Pusch, K. L. Tsakmakidis, J. M. Hamm, and O. Hess, “Overcoming losses with gain in a negative refractive index metamaterial,” Phys. Rev. Lett. 105, 127401 (2010).

[Crossref]
[PubMed]

C. M. Bender, D. C. Brody, and H. F. Jones, “Complex extension of quantum mechanics,” Phys. Rev. Lett. 89, 270401 (2002).

[Crossref]

C. M. Bender and S. Boettcher, “Real Spectra in Non-Hermitian Hamiltonians Having PT-Symmetry,” Phys. Rev. Lett. 80, 5243 (1998).

[Crossref]

S. M. Barnett, J. Jeffers, A. Gatti, and R. Loudon, “Quantum optics of lossy beam splitters,” Phys. Rev. A 57, 2134 (1998).

[Crossref]

V. Achilleos, G. Theocharis, O. Richoux, and V. Pagneux, “Non-hermitian acoustic metamaterials: Role of exceptional points in sound absorption,” Phys. Rev. B 95, 144303 (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,” Nature Materials 12, 108 (2012).

[Crossref]
[PubMed]

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

[Crossref]

P. Ambichl, K. G. Makris, L. Ge, Y. Chong, A. D. Stone, and S. Rotter, “Breaking of PT symmetry in bounded and unbounded scattering systems,” Phys. Rev. X 3, 041030 (2013).

J.-H. Wu, M. Artoni, and G. C. La Rocca, “Coherent perfect absorption in one-sided reflectionless media,” Scientific Reports 6, 35356 (2016).

[Crossref]
[PubMed]

J.-H. Wu, M. Artoni, and G. C. La Rocca, “Non-hermitian degeneracies and unidirectional reflectionless atomic lattices,” Phys. Rev. Lett. 113, 123004 (2014).

[Crossref]
[PubMed]

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

[Crossref]

S. M. Barnett, J. Jeffers, A. Gatti, and R. Loudon, “Quantum optics of lossy beam splitters,” Phys. Rev. A 57, 2134 (1998).

[Crossref]

C. M. Bender, D. C. Brody, and H. F. Jones, “Complex extension of quantum mechanics,” Phys. Rev. Lett. 89, 270401 (2002).

[Crossref]

C. M. Bender and S. Boettcher, “Real Spectra in Non-Hermitian Hamiltonians Having PT-Symmetry,” Phys. Rev. Lett. 80, 5243 (1998).

[Crossref]

A. Regensburger, C. Bersch, M.-A. Miri, G. Onishchukov, D. N. Christodoulides, and U. Peschel, “Parity-time synthetic photonic lattices,” Nature 488, 167 (2012).

[Crossref]
[PubMed]

C. M. Bender and S. Boettcher, “Real Spectra in Non-Hermitian Hamiltonians Having PT-Symmetry,” Phys. Rev. Lett. 80, 5243 (1998).

[Crossref]

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,” Nature Communications 6, 7031 (2015).

[Crossref]
[PubMed]

C. M. Bender, D. C. Brody, and H. F. Jones, “Complex extension of quantum mechanics,” Phys. Rev. Lett. 89, 270401 (2002).

[Crossref]

Z. Lin, H. Ramezani, T. Eichelkraut, T. Kottos, H. Cao, and D. N. Christodoulides, “Unidirectional invisibility induced by PT-symmetric periodic structures,” Phys. Rev. Lett. 106, 213901 (2011).

[Crossref]
[PubMed]

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

[Crossref]
[PubMed]

Y. D. Chong, L. Ge, H. Cao, and A. D. Stone, “Coherent perfect absorbers: Time-reversed lasers,” Phys. Rev. Lett. 105, 053901 (2010).

[Crossref]
[PubMed]

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]
[PubMed]

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]
[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,” Nature Materials 12, 108 (2012).

[Crossref]
[PubMed]

S. Xiao, V. P. Drachev, A. V. Kildishev, X. Ni, U. K. Chettiar, H.-K. Yuan, and V. M. Shalaev, “Loss-free and active optical negative-index metamaterials,” Nature 466, 735 (2010).

[Crossref]
[PubMed]

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

[Crossref]

P. Ambichl, K. G. Makris, L. Ge, Y. Chong, A. D. Stone, and S. Rotter, “Breaking of PT symmetry in bounded and unbounded scattering systems,” Phys. Rev. X 3, 041030 (2013).

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

[Crossref]
[PubMed]

Y. D. Chong, L. Ge, and A. D. Stone, “PT-symmetry breaking and laser-absorber modes in optical scattering systems,” Phys. Rev. Lett. 106, 093902 (2011).

[Crossref]
[PubMed]

Y. D. Chong, L. Ge, H. Cao, and A. D. Stone, “Coherent perfect absorbers: Time-reversed lasers,” Phys. Rev. Lett. 105, 053901 (2010).

[Crossref]
[PubMed]

L. Ge, K. G. Makris, D. N. Christodoulides, and L. Feng, “Scattering in PT- and RT-symmetric multimode waveguides: Generalized conservation laws and spontaneous symmetry breaking,” Phys. Rev. A 92, 062135 (2015).

[Crossref]

A. Regensburger, C. Bersch, M.-A. Miri, G. Onishchukov, D. N. Christodoulides, and U. Peschel, “Parity-time synthetic photonic lattices,” Nature 488, 167 (2012).

[Crossref]
[PubMed]

Z. Lin, H. Ramezani, T. Eichelkraut, T. Kottos, H. Cao, and D. N. Christodoulides, “Unidirectional invisibility induced by PT-symmetric periodic structures,” Phys. Rev. Lett. 106, 213901 (2011).

[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]
[PubMed]

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,” Nature Communications 6, 7031 (2015).

[Crossref]
[PubMed]

G. C. R. Devarapu and S. Foteinopoulou, “Broadband near-unidirectional absorption enabled by phonon-polariton resonances in SiC micropyramid arrays,” Phys. Rev. Applied 7, 034001 (2017).

[Crossref]

S. Xiao, V. P. Drachev, A. V. Kildishev, X. Ni, U. K. Chettiar, H.-K. Yuan, and V. M. Shalaev, “Loss-free and active optical negative-index metamaterials,” Nature 466, 735 (2010).

[Crossref]
[PubMed]

Z. Lin, H. Ramezani, T. Eichelkraut, T. Kottos, H. Cao, and D. N. Christodoulides, “Unidirectional invisibility induced by PT-symmetric periodic structures,” Phys. Rev. Lett. 106, 213901 (2011).

[Crossref]
[PubMed]

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,” Nature Communications 6, 7031 (2015).

[Crossref]
[PubMed]

H. Zhao, W. Fegadolli, J. Yu, Z. Zhang, L. Ge, A. Scherer, and L. Feng, “Metawaveguide for asymmetric interferometric light-light switching,” Phys. Rev. Lett. 117, 193901 (2016).

[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,” Nature Materials 12, 108 (2012).

[Crossref]
[PubMed]

L. Ge and L. Feng, “Contrasting eigenvalue and singular-value spectra for lasing and antilasing in a PT-symmetric periodic structure,” Phys. Rev. A 95, 013813 (2017).

[Crossref]

L. Ge and L. Feng, “Optical-reciprocity-induced symmetry in photonic heterostructures and its manifestation in scattering PT-symmetry breaking,” Phys. Rev. A 94, 043836 (2016).

[Crossref]

Z. J. Wong, Y.-L. Xu, J. Kim, K. O’Brien, Y. Wang, L. Feng, and X. Zhang, “Lasing and anti-lasing in a single cavity,” Nature Photonics 10, 796 (2016).

[Crossref]

H. Zhao, W. Fegadolli, J. Yu, Z. Zhang, L. Ge, A. Scherer, and L. Feng, “Metawaveguide for asymmetric interferometric light-light switching,” Phys. Rev. Lett. 117, 193901 (2016).

[Crossref]
[PubMed]

L. Ge, K. G. Makris, D. N. Christodoulides, and L. Feng, “Scattering in PT- and RT-symmetric multimode waveguides: Generalized conservation laws and spontaneous symmetry breaking,” Phys. Rev. A 92, 062135 (2015).

[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,” Nature Materials 12, 108 (2012).

[Crossref]
[PubMed]

G. C. R. Devarapu and S. Foteinopoulou, “Broadband near-unidirectional absorption enabled by phonon-polariton resonances in SiC micropyramid arrays,” Phys. Rev. Applied 7, 034001 (2017).

[Crossref]

S. M. Barnett, J. Jeffers, A. Gatti, and R. Loudon, “Quantum optics of lossy beam splitters,” Phys. Rev. A 57, 2134 (1998).

[Crossref]

L. Ge and L. Feng, “Contrasting eigenvalue and singular-value spectra for lasing and antilasing in a PT-symmetric periodic structure,” Phys. Rev. A 95, 013813 (2017).

[Crossref]

L. Ge and L. Feng, “Optical-reciprocity-induced symmetry in photonic heterostructures and its manifestation in scattering PT-symmetry breaking,” Phys. Rev. A 94, 043836 (2016).

[Crossref]

H. Zhao, W. Fegadolli, J. Yu, Z. Zhang, L. Ge, A. Scherer, and L. Feng, “Metawaveguide for asymmetric interferometric light-light switching,” Phys. Rev. Lett. 117, 193901 (2016).

[Crossref]
[PubMed]

L. Ge, K. G. Makris, D. N. Christodoulides, and L. Feng, “Scattering in PT- and RT-symmetric multimode waveguides: Generalized conservation laws and spontaneous symmetry breaking,” Phys. Rev. A 92, 062135 (2015).

[Crossref]

P. Ambichl, K. G. Makris, L. Ge, Y. Chong, A. D. Stone, and S. Rotter, “Breaking of PT symmetry in bounded and unbounded scattering systems,” Phys. Rev. X 3, 041030 (2013).

Y. D. Chong, L. Ge, and A. D. Stone, “PT-symmetry breaking and laser-absorber modes in optical scattering systems,” Phys. Rev. Lett. 106, 093902 (2011).

[Crossref]
[PubMed]

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

[Crossref]
[PubMed]

Y. D. Chong, L. Ge, H. Cao, and A. D. Stone, “Coherent perfect absorbers: Time-reversed lasers,” Phys. Rev. Lett. 105, 053901 (2010).

[Crossref]
[PubMed]

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]
[PubMed]

S. Wuestner, A. Pusch, K. L. Tsakmakidis, J. M. Hamm, and O. Hess, “Overcoming losses with gain in a negative refractive index metamaterial,” Phys. Rev. Lett. 105, 127401 (2010).

[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]
[PubMed]

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,” Nature Communications 6, 7031 (2015).

[Crossref]
[PubMed]

S. Wuestner, A. Pusch, K. L. Tsakmakidis, J. M. Hamm, and O. Hess, “Overcoming losses with gain in a negative refractive index metamaterial,” Phys. Rev. Lett. 105, 127401 (2010).

[Crossref]
[PubMed]

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,” Nature Communications 6, 7031 (2015).

[Crossref]
[PubMed]

S. M. Barnett, J. Jeffers, A. Gatti, and R. Loudon, “Quantum optics of lossy beam splitters,” Phys. Rev. A 57, 2134 (1998).

[Crossref]

C. M. Bender, D. C. Brody, and H. F. Jones, “Complex extension of quantum mechanics,” Phys. Rev. Lett. 89, 270401 (2002).

[Crossref]

S. Xiao, V. P. Drachev, A. V. Kildishev, X. Ni, U. K. Chettiar, H.-K. Yuan, and V. M. Shalaev, “Loss-free and active optical negative-index metamaterials,” Nature 466, 735 (2010).

[Crossref]
[PubMed]

Z. J. Wong, Y.-L. Xu, J. Kim, K. O’Brien, Y. Wang, L. Feng, and X. Zhang, “Lasing and anti-lasing in a single cavity,” Nature Photonics 10, 796 (2016).

[Crossref]

Z. Lin, H. Ramezani, T. Eichelkraut, T. Kottos, H. Cao, and D. N. Christodoulides, “Unidirectional invisibility induced by PT-symmetric periodic structures,” Phys. Rev. Lett. 106, 213901 (2011).

[Crossref]
[PubMed]

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

[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]
[PubMed]

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,” Nature Communications 6, 7031 (2015).

[Crossref]
[PubMed]

Z. Lin, H. Ramezani, T. Eichelkraut, T. Kottos, H. Cao, and D. N. Christodoulides, “Unidirectional invisibility induced by PT-symmetric periodic structures,” Phys. Rev. Lett. 106, 213901 (2011).

[Crossref]
[PubMed]

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]
[PubMed]

S. Longhi, “PT-symmetric laser absorber,” Phys. Rev. A 82, 031801 (2010).

[Crossref]

S. M. Barnett, J. Jeffers, A. Gatti, and R. Loudon, “Quantum optics of lossy beam splitters,” Phys. Rev. A 57, 2134 (1998).

[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,” Nature Materials 12, 108 (2012).

[Crossref]
[PubMed]

L. Ge, K. G. Makris, D. N. Christodoulides, and L. Feng, “Scattering in PT- and RT-symmetric multimode waveguides: Generalized conservation laws and spontaneous symmetry breaking,” Phys. Rev. A 92, 062135 (2015).

[Crossref]

P. Ambichl, K. G. Makris, L. Ge, Y. Chong, A. D. Stone, and S. Rotter, “Breaking of PT symmetry in bounded and unbounded scattering systems,” Phys. Rev. X 3, 041030 (2013).

A. Regensburger, C. Bersch, M.-A. Miri, G. Onishchukov, D. N. Christodoulides, and U. Peschel, “Parity-time synthetic photonic lattices,” Nature 488, 167 (2012).

[Crossref]
[PubMed]

S. Xiao, V. P. Drachev, A. V. Kildishev, X. Ni, U. K. Chettiar, H.-K. Yuan, and V. M. Shalaev, “Loss-free and active optical negative-index metamaterials,” Nature 466, 735 (2010).

[Crossref]
[PubMed]

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

[Crossref]
[PubMed]

Z. J. Wong, Y.-L. Xu, J. Kim, K. O’Brien, Y. Wang, L. Feng, and X. Zhang, “Lasing and anti-lasing in a single cavity,” Nature Photonics 10, 796 (2016).

[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,” Nature Materials 12, 108 (2012).

[Crossref]
[PubMed]

A. Regensburger, C. Bersch, M.-A. Miri, G. Onishchukov, D. N. Christodoulides, and U. Peschel, “Parity-time synthetic photonic lattices,” Nature 488, 167 (2012).

[Crossref]
[PubMed]

V. Achilleos, G. Theocharis, O. Richoux, and V. Pagneux, “Non-hermitian acoustic metamaterials: Role of exceptional points in sound absorption,” Phys. Rev. B 95, 144303 (2017).

[Crossref]

A. Regensburger, C. Bersch, M.-A. Miri, G. Onishchukov, D. N. Christodoulides, and U. Peschel, “Parity-time synthetic photonic lattices,” Nature 488, 167 (2012).

[Crossref]
[PubMed]

S. Wuestner, A. Pusch, K. L. Tsakmakidis, J. M. Hamm, and O. Hess, “Overcoming losses with gain in a negative refractive index metamaterial,” Phys. Rev. Lett. 105, 127401 (2010).

[Crossref]
[PubMed]

Z. Lin, H. Ramezani, T. Eichelkraut, T. Kottos, H. Cao, and D. N. Christodoulides, “Unidirectional invisibility induced by PT-symmetric periodic structures,” Phys. Rev. Lett. 106, 213901 (2011).

[Crossref]
[PubMed]

A. Regensburger, C. Bersch, M.-A. Miri, G. Onishchukov, D. N. Christodoulides, and U. Peschel, “Parity-time synthetic photonic lattices,” Nature 488, 167 (2012).

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