X. Yin and X. Zhang, “Unidirectional light propagation at exceptional points,” Nat. Mater. 12, 175–177 (2013).

[CrossRef]
[PubMed]

M. Liertzer, L. Ge, A. Cerjan, A. D. Stone, H. E. Türeci, and S. Rotter, “Pump-induced exceptional points in lasers,” Phys. Rev. Lett. 108, 173901 (2012).

[CrossRef]
[PubMed]

S. Y. Lee, J. W. Ryu, S. W. Kim, and Y. Chung, “Geometric phase around multiple exceptional points,” Phys. Rev. A 85, 064103 (2012).

[CrossRef]

B. Dietz, H. L. Harney, O. N. Kirillov, M. Miski-Oglu, A. Richter, and F. Schäfer, “Exceptional points in a microwave billiard with time-reversal invariance violation,” Phys. Rev. Lett. 106, 150403 (2011).

[CrossRef]
[PubMed]

J. Wiersig, A. Eberspächer, J. B. Shim, J. W. Ryu, S. Shinohara, M. Hentschel, and H. Schomerus, “Nonorthogonal pairs of copropagating optical modes in deformed microdisk cavities,” Phys. Rev. A 84, 023845 (2011).

[CrossRef]

Q. H. Song and H. Cao, “Improving optical confinement in nanostructures via external mode coupling,” Phys. Rev. Lett. 105, 053902 (2010).

[CrossRef]
[PubMed]

J. W. Ryu, S. Y. Lee, and S. W. Kim, “Coupled nonidentical microdisks: avoided crossing of energy levels and unidirectional far-field emission,” Phys. Rev. A 79, 053858 (2009).

[CrossRef]

N. Liu, L. Langguth, T. Weiss, J. Kästel, M. Fleischhauer, T. Pfau, and H. Giessen, “Plasmonic analogue of electromagnetically induced transparency at the Drude damping limit,” Nat. Mater. 8, 758–762 (2009).

[CrossRef]
[PubMed]

C. Cheng, J. Chen, D. J. Shi, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, J. P. Ding, and H. T. Wang, “Physical mechanism of extraordinary electromagnetic transmission in dual-metallic grating structures,” Phys. Rev. B 78, 075406 (2008).

[CrossRef]

S. Zhang, D. A. Genov, Y. Wang, M. Liu, and X. Zhang, “Plasmon-induced transparency in metamaterials,” Phys. Rev. Lett. 101, 047401 (2008).

[CrossRef]
[PubMed]

J. Wiersig, S. W. Kim, and M. Hentschel, “Asymmetric scattering and nonorthogonal mode patterns in optical microspirals,” Phys. Rev. A 78, 053809 (2008).

[CrossRef]

B. Dietz, T. Friedrich, J. Metz, M. Miski-Oglu, A. Richter, F. Schäfer, and C. A. Stafford, “Rabi oscillations at exceptional points in microwave billiards,” Phys. Rev. E 75, 027201 (2007).

[CrossRef]

C. Cheng, J. Chen, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, and H. T. Wang, “Controllable electromagnetic transmission based on dual-metallic grating structures composed of subwavelength slits,” Appl. Phys. Lett. 91, 111111 (2007).

[CrossRef]

J. Wiersig, “Formation of long-lived, scarlike modes near avoided resonance crossings in optical microcavities,” Phys. Rev. Lett. 97, 253901 (2006).

[CrossRef]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).

[CrossRef]
[PubMed]

A. A. Mailybaev, O. N. Kirillov, and A. P. Seyranian, “Geometric phase around exceptional points,” Phys. Rev. A 72, 014104 (2005).

[CrossRef]

E. Prodan, C. Radloff, N. J. Halas, and P. Nordlander, “A hybridization model for the plasmon response of complex nanostructures,” Science 302, 419–422 (2003).

[CrossRef]
[PubMed]

R. A. Shelby, D. R. Smith, and S. Schultz, “Experimental verification of a negative index of refraction,” Science 292, 77–79 (2001).

[CrossRef]
[PubMed]

W. D. Heiss and H. L. Harney, “The chirality of exceptional points,” Eur. Phys. J. D 17, 149–151 (2001).

[CrossRef]

C. Dembowski, H. D. Gräf, H. L. Harney, A. Heine, W. D. Heiss, H. Rehfeld, and A. Richter, “Experimental observation of the topological structure of exceptional points,” Phys. Rev. Lett. 86, 787–790 (2001).

[CrossRef]
[PubMed]

W. D. Heiss, “Repulsion of resonance states and exceptional points,” Phys. Rev. E 61, 929–932 (2000).

[CrossRef]

W. D. Heiss, “Phases of wave functions and level repulsion,” Eur. Phys. J. D 7, 1–4 (1999).

[CrossRef]

T. W. Ebbesen, H. J. Lezec, H. F. Ghaemi, T. Thio, and P. A. Wolff, “Extraordinary optical transmission through sub-wavelength hole arrays,” Nature 391, 667–669 (1998).

[CrossRef]

W. D. Heiss and A. L. Sannino, “Avoided level crossing and exceptional points,” J. Phys. A: Math. Gen. 23, 1167–1178 (1990).

[CrossRef]

Q. H. Song and H. Cao, “Improving optical confinement in nanostructures via external mode coupling,” Phys. Rev. Lett. 105, 053902 (2010).

[CrossRef]
[PubMed]

M. Liertzer, L. Ge, A. Cerjan, A. D. Stone, H. E. Türeci, and S. Rotter, “Pump-induced exceptional points in lasers,” Phys. Rev. Lett. 108, 173901 (2012).

[CrossRef]
[PubMed]

C. Cheng, J. Chen, D. J. Shi, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, J. P. Ding, and H. T. Wang, “Physical mechanism of extraordinary electromagnetic transmission in dual-metallic grating structures,” Phys. Rev. B 78, 075406 (2008).

[CrossRef]

C. Cheng, J. Chen, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, and H. T. Wang, “Controllable electromagnetic transmission based on dual-metallic grating structures composed of subwavelength slits,” Appl. Phys. Lett. 91, 111111 (2007).

[CrossRef]

C. Cheng, J. Chen, D. J. Shi, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, J. P. Ding, and H. T. Wang, “Physical mechanism of extraordinary electromagnetic transmission in dual-metallic grating structures,” Phys. Rev. B 78, 075406 (2008).

[CrossRef]

C. Cheng, J. Chen, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, and H. T. Wang, “Controllable electromagnetic transmission based on dual-metallic grating structures composed of subwavelength slits,” Appl. Phys. Lett. 91, 111111 (2007).

[CrossRef]

S. Y. Lee, J. W. Ryu, S. W. Kim, and Y. Chung, “Geometric phase around multiple exceptional points,” Phys. Rev. A 85, 064103 (2012).

[CrossRef]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).

[CrossRef]
[PubMed]

C. Dembowski, H. D. Gräf, H. L. Harney, A. Heine, W. D. Heiss, H. Rehfeld, and A. Richter, “Experimental observation of the topological structure of exceptional points,” Phys. Rev. Lett. 86, 787–790 (2001).

[CrossRef]
[PubMed]

B. Dietz, H. L. Harney, O. N. Kirillov, M. Miski-Oglu, A. Richter, and F. Schäfer, “Exceptional points in a microwave billiard with time-reversal invariance violation,” Phys. Rev. Lett. 106, 150403 (2011).

[CrossRef]
[PubMed]

B. Dietz, T. Friedrich, J. Metz, M. Miski-Oglu, A. Richter, F. Schäfer, and C. A. Stafford, “Rabi oscillations at exceptional points in microwave billiards,” Phys. Rev. E 75, 027201 (2007).

[CrossRef]

C. Cheng, J. Chen, D. J. Shi, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, J. P. Ding, and H. T. Wang, “Physical mechanism of extraordinary electromagnetic transmission in dual-metallic grating structures,” Phys. Rev. B 78, 075406 (2008).

[CrossRef]

T. W. Ebbesen, H. J. Lezec, H. F. Ghaemi, T. Thio, and P. A. Wolff, “Extraordinary optical transmission through sub-wavelength hole arrays,” Nature 391, 667–669 (1998).

[CrossRef]

J. Wiersig, A. Eberspächer, J. B. Shim, J. W. Ryu, S. Shinohara, M. Hentschel, and H. Schomerus, “Nonorthogonal pairs of copropagating optical modes in deformed microdisk cavities,” Phys. Rev. A 84, 023845 (2011).

[CrossRef]

C. Cheng, J. Chen, D. J. Shi, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, J. P. Ding, and H. T. Wang, “Physical mechanism of extraordinary electromagnetic transmission in dual-metallic grating structures,” Phys. Rev. B 78, 075406 (2008).

[CrossRef]

C. Cheng, J. Chen, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, and H. T. Wang, “Controllable electromagnetic transmission based on dual-metallic grating structures composed of subwavelength slits,” Appl. Phys. Lett. 91, 111111 (2007).

[CrossRef]

N. Liu, L. Langguth, T. Weiss, J. Kästel, M. Fleischhauer, T. Pfau, and H. Giessen, “Plasmonic analogue of electromagnetically induced transparency at the Drude damping limit,” Nat. Mater. 8, 758–762 (2009).

[CrossRef]
[PubMed]

B. Dietz, T. Friedrich, J. Metz, M. Miski-Oglu, A. Richter, F. Schäfer, and C. A. Stafford, “Rabi oscillations at exceptional points in microwave billiards,” Phys. Rev. E 75, 027201 (2007).

[CrossRef]

M. Liertzer, L. Ge, A. Cerjan, A. D. Stone, H. E. Türeci, and S. Rotter, “Pump-induced exceptional points in lasers,” Phys. Rev. Lett. 108, 173901 (2012).

[CrossRef]
[PubMed]

S. Zhang, D. A. Genov, Y. Wang, M. Liu, and X. Zhang, “Plasmon-induced transparency in metamaterials,” Phys. Rev. Lett. 101, 047401 (2008).

[CrossRef]
[PubMed]

T. W. Ebbesen, H. J. Lezec, H. F. Ghaemi, T. Thio, and P. A. Wolff, “Extraordinary optical transmission through sub-wavelength hole arrays,” Nature 391, 667–669 (1998).

[CrossRef]

N. Liu, L. Langguth, T. Weiss, J. Kästel, M. Fleischhauer, T. Pfau, and H. Giessen, “Plasmonic analogue of electromagnetically induced transparency at the Drude damping limit,” Nat. Mater. 8, 758–762 (2009).

[CrossRef]
[PubMed]

C. Dembowski, H. D. Gräf, H. L. Harney, A. Heine, W. D. Heiss, H. Rehfeld, and A. Richter, “Experimental observation of the topological structure of exceptional points,” Phys. Rev. Lett. 86, 787–790 (2001).

[CrossRef]
[PubMed]

E. Prodan, C. Radloff, N. J. Halas, and P. Nordlander, “A hybridization model for the plasmon response of complex nanostructures,” Science 302, 419–422 (2003).

[CrossRef]
[PubMed]

B. Dietz, H. L. Harney, O. N. Kirillov, M. Miski-Oglu, A. Richter, and F. Schäfer, “Exceptional points in a microwave billiard with time-reversal invariance violation,” Phys. Rev. Lett. 106, 150403 (2011).

[CrossRef]
[PubMed]

W. D. Heiss and H. L. Harney, “The chirality of exceptional points,” Eur. Phys. J. D 17, 149–151 (2001).

[CrossRef]

C. Dembowski, H. D. Gräf, H. L. Harney, A. Heine, W. D. Heiss, H. Rehfeld, and A. Richter, “Experimental observation of the topological structure of exceptional points,” Phys. Rev. Lett. 86, 787–790 (2001).

[CrossRef]
[PubMed]

C. Dembowski, H. D. Gräf, H. L. Harney, A. Heine, W. D. Heiss, H. Rehfeld, and A. Richter, “Experimental observation of the topological structure of exceptional points,” Phys. Rev. Lett. 86, 787–790 (2001).

[CrossRef]
[PubMed]

C. Dembowski, H. D. Gräf, H. L. Harney, A. Heine, W. D. Heiss, H. Rehfeld, and A. Richter, “Experimental observation of the topological structure of exceptional points,” Phys. Rev. Lett. 86, 787–790 (2001).

[CrossRef]
[PubMed]

W. D. Heiss and H. L. Harney, “The chirality of exceptional points,” Eur. Phys. J. D 17, 149–151 (2001).

[CrossRef]

W. D. Heiss, “Repulsion of resonance states and exceptional points,” Phys. Rev. E 61, 929–932 (2000).

[CrossRef]

W. D. Heiss, “Phases of wave functions and level repulsion,” Eur. Phys. J. D 7, 1–4 (1999).

[CrossRef]

W. D. Heiss and A. L. Sannino, “Avoided level crossing and exceptional points,” J. Phys. A: Math. Gen. 23, 1167–1178 (1990).

[CrossRef]

J. Wiersig, A. Eberspächer, J. B. Shim, J. W. Ryu, S. Shinohara, M. Hentschel, and H. Schomerus, “Nonorthogonal pairs of copropagating optical modes in deformed microdisk cavities,” Phys. Rev. A 84, 023845 (2011).

[CrossRef]

J. Wiersig, S. W. Kim, and M. Hentschel, “Asymmetric scattering and nonorthogonal mode patterns in optical microspirals,” Phys. Rev. A 78, 053809 (2008).

[CrossRef]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).

[CrossRef]
[PubMed]

N. Liu, L. Langguth, T. Weiss, J. Kästel, M. Fleischhauer, T. Pfau, and H. Giessen, “Plasmonic analogue of electromagnetically induced transparency at the Drude damping limit,” Nat. Mater. 8, 758–762 (2009).

[CrossRef]
[PubMed]

S. Y. Lee, J. W. Ryu, S. W. Kim, and Y. Chung, “Geometric phase around multiple exceptional points,” Phys. Rev. A 85, 064103 (2012).

[CrossRef]

J. W. Ryu, S. Y. Lee, and S. W. Kim, “Coupled nonidentical microdisks: avoided crossing of energy levels and unidirectional far-field emission,” Phys. Rev. A 79, 053858 (2009).

[CrossRef]

J. Wiersig, S. W. Kim, and M. Hentschel, “Asymmetric scattering and nonorthogonal mode patterns in optical microspirals,” Phys. Rev. A 78, 053809 (2008).

[CrossRef]

B. Dietz, H. L. Harney, O. N. Kirillov, M. Miski-Oglu, A. Richter, and F. Schäfer, “Exceptional points in a microwave billiard with time-reversal invariance violation,” Phys. Rev. Lett. 106, 150403 (2011).

[CrossRef]
[PubMed]

A. A. Mailybaev, O. N. Kirillov, and A. P. Seyranian, “Geometric phase around exceptional points,” Phys. Rev. A 72, 014104 (2005).

[CrossRef]

N. Liu, L. Langguth, T. Weiss, J. Kästel, M. Fleischhauer, T. Pfau, and H. Giessen, “Plasmonic analogue of electromagnetically induced transparency at the Drude damping limit,” Nat. Mater. 8, 758–762 (2009).

[CrossRef]
[PubMed]

S. Y. Lee, J. W. Ryu, S. W. Kim, and Y. Chung, “Geometric phase around multiple exceptional points,” Phys. Rev. A 85, 064103 (2012).

[CrossRef]

J. W. Ryu, S. Y. Lee, and S. W. Kim, “Coupled nonidentical microdisks: avoided crossing of energy levels and unidirectional far-field emission,” Phys. Rev. A 79, 053858 (2009).

[CrossRef]

T. W. Ebbesen, H. J. Lezec, H. F. Ghaemi, T. Thio, and P. A. Wolff, “Extraordinary optical transmission through sub-wavelength hole arrays,” Nature 391, 667–669 (1998).

[CrossRef]

M. Liertzer, L. Ge, A. Cerjan, A. D. Stone, H. E. Türeci, and S. Rotter, “Pump-induced exceptional points in lasers,” Phys. Rev. Lett. 108, 173901 (2012).

[CrossRef]
[PubMed]

S. Zhang, D. A. Genov, Y. Wang, M. Liu, and X. Zhang, “Plasmon-induced transparency in metamaterials,” Phys. Rev. Lett. 101, 047401 (2008).

[CrossRef]
[PubMed]

N. Liu, L. Langguth, T. Weiss, J. Kästel, M. Fleischhauer, T. Pfau, and H. Giessen, “Plasmonic analogue of electromagnetically induced transparency at the Drude damping limit,” Nat. Mater. 8, 758–762 (2009).

[CrossRef]
[PubMed]

A. A. Mailybaev, O. N. Kirillov, and A. P. Seyranian, “Geometric phase around exceptional points,” Phys. Rev. A 72, 014104 (2005).

[CrossRef]

B. Dietz, T. Friedrich, J. Metz, M. Miski-Oglu, A. Richter, F. Schäfer, and C. A. Stafford, “Rabi oscillations at exceptional points in microwave billiards,” Phys. Rev. E 75, 027201 (2007).

[CrossRef]

B. Dietz, H. L. Harney, O. N. Kirillov, M. Miski-Oglu, A. Richter, and F. Schäfer, “Exceptional points in a microwave billiard with time-reversal invariance violation,” Phys. Rev. Lett. 106, 150403 (2011).

[CrossRef]
[PubMed]

B. Dietz, T. Friedrich, J. Metz, M. Miski-Oglu, A. Richter, F. Schäfer, and C. A. Stafford, “Rabi oscillations at exceptional points in microwave billiards,” Phys. Rev. E 75, 027201 (2007).

[CrossRef]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).

[CrossRef]
[PubMed]

N. Moiseyev, Non-Hermitian Quantum Mechanics(Cambridge University Press, 2011).

[CrossRef]

E. Prodan, C. Radloff, N. J. Halas, and P. Nordlander, “A hybridization model for the plasmon response of complex nanostructures,” Science 302, 419–422 (2003).

[CrossRef]
[PubMed]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).

[CrossRef]
[PubMed]

N. Liu, L. Langguth, T. Weiss, J. Kästel, M. Fleischhauer, T. Pfau, and H. Giessen, “Plasmonic analogue of electromagnetically induced transparency at the Drude damping limit,” Nat. Mater. 8, 758–762 (2009).

[CrossRef]
[PubMed]

E. Prodan, C. Radloff, N. J. Halas, and P. Nordlander, “A hybridization model for the plasmon response of complex nanostructures,” Science 302, 419–422 (2003).

[CrossRef]
[PubMed]

E. Prodan, C. Radloff, N. J. Halas, and P. Nordlander, “A hybridization model for the plasmon response of complex nanostructures,” Science 302, 419–422 (2003).

[CrossRef]
[PubMed]

C. Dembowski, H. D. Gräf, H. L. Harney, A. Heine, W. D. Heiss, H. Rehfeld, and A. Richter, “Experimental observation of the topological structure of exceptional points,” Phys. Rev. Lett. 86, 787–790 (2001).

[CrossRef]
[PubMed]

C. Cheng, J. Chen, D. J. Shi, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, J. P. Ding, and H. T. Wang, “Physical mechanism of extraordinary electromagnetic transmission in dual-metallic grating structures,” Phys. Rev. B 78, 075406 (2008).

[CrossRef]

C. Cheng, J. Chen, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, and H. T. Wang, “Controllable electromagnetic transmission based on dual-metallic grating structures composed of subwavelength slits,” Appl. Phys. Lett. 91, 111111 (2007).

[CrossRef]

B. Dietz, H. L. Harney, O. N. Kirillov, M. Miski-Oglu, A. Richter, and F. Schäfer, “Exceptional points in a microwave billiard with time-reversal invariance violation,” Phys. Rev. Lett. 106, 150403 (2011).

[CrossRef]
[PubMed]

B. Dietz, T. Friedrich, J. Metz, M. Miski-Oglu, A. Richter, F. Schäfer, and C. A. Stafford, “Rabi oscillations at exceptional points in microwave billiards,” Phys. Rev. E 75, 027201 (2007).

[CrossRef]

C. Dembowski, H. D. Gräf, H. L. Harney, A. Heine, W. D. Heiss, H. Rehfeld, and A. Richter, “Experimental observation of the topological structure of exceptional points,” Phys. Rev. Lett. 86, 787–790 (2001).

[CrossRef]
[PubMed]

M. Liertzer, L. Ge, A. Cerjan, A. D. Stone, H. E. Türeci, and S. Rotter, “Pump-induced exceptional points in lasers,” Phys. Rev. Lett. 108, 173901 (2012).

[CrossRef]
[PubMed]

S. Y. Lee, J. W. Ryu, S. W. Kim, and Y. Chung, “Geometric phase around multiple exceptional points,” Phys. Rev. A 85, 064103 (2012).

[CrossRef]

J. Wiersig, A. Eberspächer, J. B. Shim, J. W. Ryu, S. Shinohara, M. Hentschel, and H. Schomerus, “Nonorthogonal pairs of copropagating optical modes in deformed microdisk cavities,” Phys. Rev. A 84, 023845 (2011).

[CrossRef]

J. W. Ryu, S. Y. Lee, and S. W. Kim, “Coupled nonidentical microdisks: avoided crossing of energy levels and unidirectional far-field emission,” Phys. Rev. A 79, 053858 (2009).

[CrossRef]

W. D. Heiss and A. L. Sannino, “Avoided level crossing and exceptional points,” J. Phys. A: Math. Gen. 23, 1167–1178 (1990).

[CrossRef]

B. Dietz, H. L. Harney, O. N. Kirillov, M. Miski-Oglu, A. Richter, and F. Schäfer, “Exceptional points in a microwave billiard with time-reversal invariance violation,” Phys. Rev. Lett. 106, 150403 (2011).

[CrossRef]
[PubMed]

B. Dietz, T. Friedrich, J. Metz, M. Miski-Oglu, A. Richter, F. Schäfer, and C. A. Stafford, “Rabi oscillations at exceptional points in microwave billiards,” Phys. Rev. E 75, 027201 (2007).

[CrossRef]

J. Wiersig, A. Eberspächer, J. B. Shim, J. W. Ryu, S. Shinohara, M. Hentschel, and H. Schomerus, “Nonorthogonal pairs of copropagating optical modes in deformed microdisk cavities,” Phys. Rev. A 84, 023845 (2011).

[CrossRef]

R. A. Shelby, D. R. Smith, and S. Schultz, “Experimental verification of a negative index of refraction,” Science 292, 77–79 (2001).

[CrossRef]
[PubMed]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).

[CrossRef]
[PubMed]

A. A. Mailybaev, O. N. Kirillov, and A. P. Seyranian, “Geometric phase around exceptional points,” Phys. Rev. A 72, 014104 (2005).

[CrossRef]

R. A. Shelby, D. R. Smith, and S. Schultz, “Experimental verification of a negative index of refraction,” Science 292, 77–79 (2001).

[CrossRef]
[PubMed]

C. Cheng, J. Chen, D. J. Shi, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, J. P. Ding, and H. T. Wang, “Physical mechanism of extraordinary electromagnetic transmission in dual-metallic grating structures,” Phys. Rev. B 78, 075406 (2008).

[CrossRef]

J. Wiersig, A. Eberspächer, J. B. Shim, J. W. Ryu, S. Shinohara, M. Hentschel, and H. Schomerus, “Nonorthogonal pairs of copropagating optical modes in deformed microdisk cavities,” Phys. Rev. A 84, 023845 (2011).

[CrossRef]

J. Wiersig, A. Eberspächer, J. B. Shim, J. W. Ryu, S. Shinohara, M. Hentschel, and H. Schomerus, “Nonorthogonal pairs of copropagating optical modes in deformed microdisk cavities,” Phys. Rev. A 84, 023845 (2011).

[CrossRef]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).

[CrossRef]
[PubMed]

R. A. Shelby, D. R. Smith, and S. Schultz, “Experimental verification of a negative index of refraction,” Science 292, 77–79 (2001).

[CrossRef]
[PubMed]

Q. H. Song and H. Cao, “Improving optical confinement in nanostructures via external mode coupling,” Phys. Rev. Lett. 105, 053902 (2010).

[CrossRef]
[PubMed]

B. Dietz, T. Friedrich, J. Metz, M. Miski-Oglu, A. Richter, F. Schäfer, and C. A. Stafford, “Rabi oscillations at exceptional points in microwave billiards,” Phys. Rev. E 75, 027201 (2007).

[CrossRef]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).

[CrossRef]
[PubMed]

M. Liertzer, L. Ge, A. Cerjan, A. D. Stone, H. E. Türeci, and S. Rotter, “Pump-induced exceptional points in lasers,” Phys. Rev. Lett. 108, 173901 (2012).

[CrossRef]
[PubMed]

T. W. Ebbesen, H. J. Lezec, H. F. Ghaemi, T. Thio, and P. A. Wolff, “Extraordinary optical transmission through sub-wavelength hole arrays,” Nature 391, 667–669 (1998).

[CrossRef]

M. Liertzer, L. Ge, A. Cerjan, A. D. Stone, H. E. Türeci, and S. Rotter, “Pump-induced exceptional points in lasers,” Phys. Rev. Lett. 108, 173901 (2012).

[CrossRef]
[PubMed]

C. Cheng, J. Chen, D. J. Shi, Q. Y. Wu, F. F. Ren, J. Xu, Y. X. Fan, J. P. Ding, and H. T. Wang, “Physical mechanism of extraordinary electromagnetic transmission in dual-metallic grating structures,” Phys. Rev. B 78, 075406 (2008).

[CrossRef]

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