English
Related papers

Related papers: Defect in Photonic Time Crystals

200 papers

Photonic time-varying systems have attracted significant attention owing to their rich physics and potential opportunities for new and enhanced functionalities. In this context, the duality of space and time in wave physics has been…

Optics · Physics 2022-09-13 Zeki Hayran , Jacob B. Khurgin , Francesco Monticone

Photonic time crystals are electromagnetic media with periodically time-varying parameters, enabling momentum band gaps, parametric amplification, and frequency conversion beyond what is possible in time-invariant systems. So far, they have…

Optics · Physics 2026-05-15 Z. Li , M. S. Mirmoosa , V. Asadchy , X. Wang

Time-varying media offer a platform to realize novel and exotic wave effects, including photonic time crystals characterized by momentum band gaps with exponential wave amplification. Here we focus on the quantum electrodynamical properties…

Lorentzian-type media support optical phonons that oscillate with longitudinal polarization parallel to the wave direction, at a wave vector-independent frequency at which the permittivity becomes zero. Here, we study the interactions…

Optics · Physics 2024-09-26 Sihao Zhang , Junhua Dong , Huanan Li , Jingjun Xu , Boris Shapiro

Photonic crystals with a sufficiently high refractive index contrast display partial or full band gaps. However, imperfections in the metamaterial cause light scattering and extinction of the interfering propagating waves. Positive as well…

Optics · Physics 2022-02-02 Stefan Aeby , Geoffroy J. Aubry , Nicolas Muller , Frank Scheffold

Exotic forms of wave control have been emerging by engineering matter in space and time. In this framework, temporal photonic interfaces, i.e., abrupt changes in the electromagnetic properties of a material, have been shown to induce…

Periodically time-varying media, known as photonic time crystals (PTCs), provide a promising platform for observing unconventional wave phenomena. We analyze the scattering of electromagnetic waves from spatially finite PTCs using the…

We demonstrate that disorder in photonic crystals could lead to pronounced modification of spontaneous emission rate in the frequency region corresponding to the photonic band gap (PBG). Depending on the amount of disorder, two different…

We demonstrated a tunable temporal gap based on simultaneous fast and slow light in electro-optic photonic crystals. The light experiences an anomalous dispersion near the transmission center and a normal dispersion away from the center,…

Optics · Physics 2017-04-20 Guangzhen Li , Yuping Chen , Haowei Jiang , Yi'an Liu , Xiao Liu , Xianfeng Chen

The realization of photonic time crystals is a major opportunity but also comes with significant challenges. The most pressing one, potentially, is the requirement for a substantial modulation strength in the material properties to create a…

Time metamaterials exhibit a great potential for wave manipulation, drawing increasing attention in recent years. Here, we explore the exotic wave dynamics in an anisotropic photonic time crystal (APTC), formed by an anisotropic medium…

Optics · Physics 2023-03-10 Huanan Li , Shixiong Yin , Huan He , Jingjun Xu , Andrea Alù , Boris Shapiro

Contact defects are time-periodic patterns in one space dimension that resemble spatially homogeneous oscillations with an embedded defect in their core region. For theoretical and numerical purposes, it is important to understand whether…

Dynamical Systems · Mathematics 2023-03-21 Milen Ivanov , Bjorn Sandstede

Topological edge states in systems of two (or more) dimensions offer scattering-free transport, exhibiting robustness to inhomogeneities and disorder. In a different domain, time-modulated systems, such as photonic time crystals (PTCs),…

We study the time-reflection and time-refraction of waves caused by a spatial interface with a medium undergoing a sudden temporal change in permittivity. We show that monochromatic waves are transformed into a pulse by the permittivity…

We investigate the spectral properties of photonic crystals, lacking parity-time (PT) symmetry, using scattering matrix formalism. We show using the symmetry properties of matrices that a defective photonic crystal, doped with three-level…

Optics · Physics 2025-02-20 Nancy Ghangas , Shubhrangshu Dasgupta

The Moir\'e superlattice has attracted growing interest in the electromagnetic and optical communities. Here, we extend this concept to time-varying photonic systems by superposing two binary modulations on the refractive index with…

Optics · Physics 2025-07-17 Zhaohui Dong , Xianfeng Chen , Luqi Yuan

The understanding of how the arrangement of defects in photonic crystals impacts its photonic properties is cru-cial for the design of functional materials based thereon. By preparing photonic crystals with random missing scatterers we…

Photonic time crystals (PTCs) - dielectric media whose permittivity is periodically modulated in time - map to a Dirac equation with an imaginary mass, opening a momentum gap (k-gap) where modes grow or decay exponentially. Here, we…

Floquet time crystals, characterized by momentum gaps (k-gaps), have sparked intense interest across various branches of physics due to their intriguing dynamics and promising applications. Despite growing theoretical efforts, the…

Applied Physics · Physics 2025-06-02 Z. Liu , X. Zhu , Z. G. Zhang , W. M. Zhang , X. Chen , Y. Q. Yang , R. W. Peng , M. Wang , J. Li , H. W. Wu

The time-dependence of the Bragg diffraction by one-dimensional photonic crystals and its influence on the short pulse reflection are studied in the framework of the coupled- wave theory. The indicial response of the photonic crystal is…

Optics · Physics 2015-09-02 Jean-michel André , Philippe Jonnard