Pendry, J. B. Negative refraction makes a perfect lens. Phys. Rev. Lett. 85, 3966–3969 (2000).
Fang, N., Lee, H., Sun, C. & Zhang, X. Sub–diffraction-limited optical imaging with a silver superlens. Science 308, 534–538 (2005).
Liu, Z., Lee, H., Xiong, Y., Sun, C. & Zhang, X. Far-field optical hyperlens magnifying sub-diffraction-limited objects. Science 315, 1686 (2007).
Taubner, T., Korobkin, D., Urzhumov, Y., Shvets, G. & Hillenbrand, R. Near-field microscopy through a SiC superlens. Science 313, 1595 (2006).
Kim, S., Peng, Y., Yves, S. & Alù, A. Loss compensation and super-resolution with excitations at complex frequencies. Phys. Rev. X 13, 041024 (2023).
Guan, F. et al. Overcoming losses in superlenses with synthetic waves of complex frequency. Science 381, 766–771 (2023).
Liu, N. et al. Plasmonic analogue of electromagnetically induced transparency at the Drude damping limit. Nat. Mater. 8, 758–762 (2009).
Liu, N., Mesch, M., Weiss, T., Hentschel, M. & Giessen, H. Infrared perfect absorber and its application as plasmonic sensor. Nano Lett. 10, 2342–2348 (2010).
Rodrigo, D. et al. Mid-infrared plasmonic biosensing with graphene. Science 349, 165–168 (2015).
Sreekanth, K. V. et al. Extreme sensitivity biosensing platform based on hyperbolic metamaterials. Nat. Mater. 15, 621–627 (2016).
Tittl, A. et al. Imaging-based molecular barcoding with pixelated dielectric metasurfaces. Science 360, 1105–1109 (2018).
Basov, D. N., Fogler, M. M. & García De Abajo, F. J. Polaritons in van der Waals materials. Science 354, aag1992 (2016).
Bozhevolnyi, S. I., Volkov, V. S., Devaux, E., Laluet, J. Y. & Ebbesen, T. W. Channel plasmon subwavelength waveguide components including interferometers and ring resonators. Nature 440, 508–511 (2006).
Oulton, R. F. et al. Plasmon lasers at deep subwavelength scale. Nature 461, 629–632 (2009).
Fei, Z. et al. Gate-tuning of graphene plasmons revealed by infrared nano-imaging. Nature 487, 82–85 (2012).
Hu, H. et al. Gate-tunable negative refraction of mid-infrared polaritons. Science 379, 558–561 (2023).
Ni, G. X. et al. Fundamental limits to graphene plasmonics. Nature 557, 530–533 (2018).
Xiao, S. et al. Loss-free and active optical negative-index metamaterials. Nature 466, 735–738 (2010).
Hamm, J. M., Wuestner, S., Tsakmakidis, K. L. & Hess, O. Theory of light amplification in active fishnet metamaterials. Phys. Rev. Lett. 107, 167405 (2011).
Sadatgol, M., Özdemir, ŞK., Yang, L. & Güney, D. O. Plasmon injection to compensate and control losses in negative index metamaterials. Phys. Rev. Lett. 115, 035502 (2015).
Archambault, A., Besbes, M. & Greffet, J. J. Superlens in the time domain. Phys. Rev. Lett. 109, 097405 (2012).
Ghoshroy, A., Özdemir, ŞK. & Güney, D. Ö Loss compensation in metamaterials and plasmonics with virtual gain [invited]. Opt. Mater. Express 10, 1862–1880 (2020).
Tetikol, H. S. & Aksun, M. I. Enhancement of resolution and propagation length by sources with temporal decay in plasmonic devices. Plasmonics 15, 2137–2146 (2020).
An, S., Liu, T., Zhu, J. & Cheng, L. Complex-frequency calculation in acoustics with real-frequency solvers. Phys. Rev. B 111, L020301 (2025).
Tsakmakidis, K. L., Pickering, T. W., Hamm, J. M., Page, A. F. & Hess, O. Completely stopped and dispersionless light in plasmonic waveguides. Phys. Rev. Lett. 112, 167401 (2014).
Baranov, D. G., Krasnok, A. & Alù, A. Coherent virtual absorption based on complex zero excitation for ideal light capturing. Optica 4, 1457–1461 (2017).
Li, H., Mekawy, A., Krasnok, A. & Alù, A. Virtual parity-time symmetry. Phys. Rev. Lett. 124, 193901 (2020).
Trainiti, G., Radi, Y., Ruzzene, M. & Alù, A. Coherent virtual absorption of elastodynamic waves. Sci. Adv. 5, eaaw3255 (2019).
Kim, S., Lepeshov, S., Krasnok, A. & Alù, A. Beyond bounds on light scattering with complex frequency excitations. Phys. Rev. Lett. 129, 203601 (2022).
Gu, Z. et al. Transient non-Hermitian skin effect. Nat. Commun. 13, 7668 (2022).
Hinney, J. et al. Efficient excitation and control of integrated photonic circuits with virtual critical coupling. Nat. Commun. 15, 2741 (2024).
Kim, S., Krasnok, A. & Alù, A. Complex-frequency excitations in photonics and wave physics. Science 387, eado4128 (2025).
Basov, D. N. & Fogler, M. M. ‘The unreasonable effectiveness of mathematics’ in evading polaritonic losses. Nat. Mater. 23, 445–446 (2024).
Cheng, Q. & Li, T. Complex-frequency waves: beat loss and win sensitivity. Light Sci. Appl. 13, 40 (2024).
Zouros, G. P., Loulas, I., Almpanis, E., Krasnok, A. & Tsakmakidis, K. L. Anisotropic virtual gain and large tuning of particles’ scattering by complex-frequency excitations. Commun. Phys. 7, 283 (2024).
Loulas, I., Psychogiou, E.-C., Tsakmakidis, K. L. & Stefanou, N. Analytic theory of complex-frequency-aided virtual absorption. Opt. Express 33, 28333–28342 (2025).
Zeng, K. et al. Synthesized complex-frequency excitation for ultrasensitive molecular sensing. eLight 4, 1 (2024).
Guan, F. et al. Compensating losses in polariton propagation with synthesized complex frequency excitation. Nat. Mater. 23, 506 (2024).
Rogov, A. & Narimanov, E. Space−time metamaterials. ACS Photonics 5, 2868–2877 (2018).
Farhi, A., Mekawy, A., Alù, A. & Stone, D. Excitation of absorbing exceptional points in the time domain. Phys. Rev. A 106, L031503 (2022).
Farhi, A., Cerjan, A. & Stone, A. D. Generating and processing optical waveforms using spectral singularities. Phys. Rev. A 109, 013512 (2024).
Farhi, A., Dai, W., Kim, S., Alù, A. & Stone, D. Efficient general waveform catching by a cavity at an absorbing exceptional point. Phys. Rev. A 109, L041502 (2024).
Fleischhauer, M., Imamoglu, A. & Marangos, P. J. Electromagnetically induced transparency: optics in coherent media. Rev. Mod. Phys. 77, 633–673 (2005).
Zhang, S., Genov, D. A., Wang, Y., Liu, M. & Zhang, X. Plasmon-induced transparency in metamaterials. Phys. Rev. Lett. 101, 047401 (2008).
Gralak, B., Lequime, M., Zerrad, M. & Amra, C. Phase retrieval of reflection and transmission coefficients from Kramers–Kronig relations. J. Opt. Soc. Am. A 32, 456–462 (2015).
Zheng, G. et al. Metasurface holograms reaching 80% efficiency. Nat. Nanotechnol. 10, 308–312 (2015).