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Related papers: Optical Spectral Singularities and Coherent Perfec…

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We propose a design for an universal absorber, characterized by a resonance frequency that can be tuned from visible to microwave frequencies independently of the choice of the metal and the dielectrics involved. An almost resonant perfect…

Critical coupling has emerged as a prominent area of research in recent years. However, most theoretical models are based on scalar theories (and occasionally coupled mode theories), which inadequately account for the polarization states of…

Optics · Physics 2025-10-09 Sauvik Roy , Nirmalya Ghosh , Ayan Banerjee , Subhasish Dutta Gupta

Short-length fiber lasers are key elements for device integration in fiber systems. However, efficiently absorbing a pump beam in a short ion-doped fiber remains a challenge. We present an approach that renders a weakly absorbing…

Optics · Physics 2017-06-16 Ali. K. Jahromi , Ayman F. Abouraddy

Fourier-based optical computing operations, such as spatial differentiation, have recently been realized in compact form factors using flat optics. Experimental demonstrations, however, have been limited to coherent light requiring laser…

Optics · Physics 2021-12-07 Xiaomeng Zhang , Benfeng Bai , Hong-Bo Sun , Guofan Jin , Jason Valentine

High-precision laser interferometric instruments require optical surfaces with a close to perfect contour, as well as low scattering and absorption. Especially point absorbers are problematic because they heat up at high optical intensities…

Optics · Physics 2023-12-20 Leif Albers , Malte Hagemann , Roman Schnabel

Optical absorption plays a central role in optoelectronic and photonic technologies. Strongly absorbing materials are thus needed for efficient and miniaturized devices. There exists, however, a fundamental limit of 50% absorptance for any…

We present a theoretical study of a spectral filter, which consists of a diffraction grating, a coupling lens, and an optical fiber. As the diffracted beam is highly dispersed spatially, coupling into an optical fiber naturally creates a…

Optics · Physics 2025-03-25 Seonjong Ryu , Jinpyo Jeong , Mintae Kang , Taemin Son , Andy Chong

Optical interferometers provide multiple wavelength measurements. In order to fully exploit the spectral and spatial resolution of these instruments, new algorithms for image reconstruction have to be developed. Early attempts to deal with…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Éric Thiébaut , Ferréol Soulez , Loïc Denis

Supersolidity of glasses is explained as a property of an unusual state of condensed matter. This state is essentially different from both normal and superfluid solid states. The mechanism of the phenomenon is the transfer of mass by…

Soft Condensed Matter · Physics 2007-05-23 A. F. Andreev

We investigate the electromagnetic response of a pair of complementary bi-anisotropic media, which consist of a medium with positive refractive index ($+\ep$, $+\mu$, $+\xi$) and a medium with negative refractive index($-\ep$, $-\mu$,…

Optics · Physics 2013-08-12 Yan Liu , Sebastien Guenneau , Boris Gralak , S. Anantha Ramakrishna

We address the question of the optimal broadband absorption of waves in an open, dissipative system. We develop a general framework for absorption induced by multiple overlapping resonances, based on quasi-normal modes and radiative and…

Optics · Physics 2024-07-30 Stéphane Collin , Maxime Giteau

We explore the scattering of waves in designed asymmetric one-dimensional waveguide networks. We show that the reflection between two ports of an asymmetric network can be identical over a broad frequency range, as if the network was…

We consider optical media which feature antilinear symmetries. We show that: (i) spectral singularities of such media (if any) are always self-dual, i.e., correspond to CPA-lasers; (ii) under the change of a system's parameter the self-dual…

Optics · Physics 2017-12-12 Vladimir V. Konotop , Dmitry A. Zezyulin

Anomalous resonances in properly shaped plasmonic nanostructures can in principle lead to infinite absorption/gain efficiencies over broad bandwidths. By developing a closed-form analytical solution for the fields scattered by conjoined…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 Nasim Mohammadi Estakhri , Andrea Alu

Optical contrast is the most common preliminary method to identify layer number of two-dimensional (2D) materials, but is seldom used as a confirmatory technique. We explain the reason for variation of optical contrast between imaging…

Optics · Physics 2022-09-12 Mainak Mondal , Ajit Kumar Dash , Akshay Singh

We show that the four-wave mixing can restrict spectral broadening. This is a general physical phenomenon that occurs in one-dimensional systems of four wave packets that resonantly interact "2-to-2": $…

Optics · Physics 2015-02-10 Alexander M. Balk

Coherent perfect absorption (CPA) has been a topic of considerable contemporary research interest. Most of the theoretical treatment of CPA with beams, to the best of our knowledge, relies on a scalar (in some cases coupled mode) theories…

Optics · Physics 2025-03-25 Sauvik Roy , Nirmalya Ghosh , Ayan Banerjee , Subhasish Dutta Gupta

The coherent stochastic resonance is observed and studied with multi-step periodic signal in continuous medium having two absorbing boundaries. The general features of this process are exihibited. The universal features at the resonance…

Condensed Matter · Physics 2009-10-31 Asish K. Dhara , Tapan Mukhopadhyay

We study the secrecy of an optical communication system with two scattering layers, to hide both the sender and receiver, by measuring the correlation of the intermediate speckle generated between the two layers. The binary message is…

Speckle is the spatial fluctuation of irradiance seen when coherent light is reflected from a rough surface. It is due to light reflected from the surface's many nooks and crannies accumulating vastly-discrepant time delays, spanning much…

Optics · Physics 2020-08-26 Justin Dove , Jeffrey H. Shapiro