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Related papers: Terahertz Microscopy Through Complex Media

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Transmission of a normally incident plane wave through a metasurface with bicontrollable subwavelength scattering elements was simulated using a commercial software. Some pixels comprising the $H-shaped scattering elements were made of a…

Optics · Physics 2018-05-23 Francesco Chiadini , Akhlesh Lakhtakia

We consider wave scattering from a system of highly contrasting resonators with time-modulated material parameters. In this setting, the wave equation reduces to a system of coupled Helmholtz equations that models the scattering problem. We…

Mathematical Physics · Physics 2024-01-05 Habib Ammari , Jinghao Cao , Erik Orvehed Hiltunen , Liora Rueff

We develop an imaging algorithm that exploits strong scattering to achieve super-resolution in changing random media. The method processes large and diverse array datasets using sparse dictionary learning, clustering, and multidimensional…

Terahertz (THz) waves have been significantly developed in the last fifteen years because of their great potential for applications in industrial and scientific communities1,2. The unique properties of THz waves as transparency for numerous…

Optics · Physics 2015-05-27 F. Blanchard , A. Doi , T. Tanaka , H. Hirori , H. Tanaka , Y. Kadoya , K. Tanaka

Adoption of terahertz technologies is hindered by the lack of cost-effective THz sources. Here we demonstrate a fundamentally new way to generate and control THz radiation, via spatio-temporal emissivity modulation. By patterning the…

We present experimental and numerical studies of localized terahertz surface waves on a subwavelength-thick metamaterial film consisting of in-plane split-ring resonators. A simple and intuitive model is derived that describes the…

Optics · Physics 2010-10-06 Benjamin Reinhard , Oliver Paul , Rene Beigang , Marco Rahm

Terahertz time domain spectroscopy employing free-space radiation has frequently been used to probe the elementary excitations of low-dimensional systems. The diffraction limit blocks its use for the in-plane study of individual laterally…

Acquiring full control over a large number of diffraction orders can be strongly attractive in the case of realizing multifunctional devices such as multichannel reflectors. Recently, the concept of metagrating has been introduced which…

Applied Physics · Physics 2020-03-18 Sahar Behroozinia , Hamid Rajabalipanah , Ali Abdolali

A time-resolved spectroscopic protocol exploiting terahertz-assisted photoionization is proposed to reconstruct transient density matrix. Population and coherence elements are effectively mapped onto spectrally separated peaks in…

Quantum Physics · Physics 2018-09-13 Yizhu Zhang , Tian-Min Yan , Y. H. Jiang

Numerous everyday situations like navigation, medical imaging and rescue operations require viewing through optically inhomogeneous media. This is a challenging task as photons, instead of traversing ballistically, propagate predominantly…

We introduce a systematic approach that enables two robust methods for performing terahertz time-domain spectroscopy in reflection geometry. Using the Kramers-Kronig relations in connection to accurate experimental measurements of the…

This work investigates the temporal dispersion of a wireless terahertz communication signal caused by reflection from a rough (diffuse) surface, and its subsequent impact on symbol error rate versus data rate. Broadband measurements of…

Signal Processing · Electrical Eng. & Systems 2021-04-02 Russ Messenger , Karl Strecker , Sabit Ekin , John O'Hara

Motivated by analogue models of classical and quantum field theory in curved spacetimes and their recent experimental realizations, we consider wave scattering processes of dispersive fields exhibiting two extra degrees of freedom. In…

General Relativity and Quantum Cosmology · Physics 2013-06-14 Maurício Richartz , Angus Prain , Silke Weinfurtner , Stefano Liberati

Retrieving information through disordered scattering systems remains a major challenge in wireless communication and sensing due to the severe distortion and attenuation caused by multiple scattering. Here, we demonstrate robust focusing…

The invisibility cloak has been a long-standing dream for many researchers over the decades. By transforming space and light propagation, a three-dimensional (3D) object can be perceived as having reduced number of dimensions, in the form…

Optics · Physics 2010-03-18 Fan Zhou , Yongjun Bao , Wei Cao , Jianqiang Gu , Weili Zhang , Cheng Sun

In this text, results of a 0.35 terahertz (THz) dynamic aperture imaging approach are presented. The experiments use an optical modulation approach and a single pixel detector at a stand-off imaging distance of approx 1 meter. The optical…

Instrumentation and Detectors · Physics 2019-02-22 Sven Augustin , Peter Jung , Sven Frohmann , Heinz-Wilhelm Huebers

Optical wavefront-shaping has emerged as a powerful tool to manipulate light in strongly scattering media. It enables diffraction-limited focusing and imaging at depths where conventional microscopy techniques fail. However, while most…

Optics · Physics 2014-03-04 T. Chaigne , O. Katz , A. C. Boccara , M. Fink , E. Bossy , S. Gigan

Recent advances in deep learning have been providing non-intuitive solutions to various inverse problems in optics. At the intersection of machine learning and optics, diffractive networks merge wave-optics with deep learning to design…

Optical imaging relies on the ability to illuminate an object, collect and analyze the light it scatters or transmits. Propagation through complex media such as biological tissues was so far believed to degrade the attainable depth as well…

Optics · Physics 2010-09-24 S. M. Popoff , G. Lerosey , M. Fink , A. C. Boccara , S. Gigan

Focusing waves inside inhomogeneous media is a fundamental problem for imaging. Spatial variations of wave velocity can strongly distort propagating wavefronts and degrade image quality. Adaptive focusing can compensate for such aberration,…

Image and Video Processing · Electrical Eng. & Systems 2020-06-15 William Lambert , Laura A. Cobus , Thomas Frappart , Mathias Fink , Alexandre Aubry