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Related papers: Tunable Plasmonic Toroidal Terahertz Metamodulator

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High spectral purity frequency agile room temperature sources in the terahertz spectrum are foundational elements for imaging, sensing, metrology, and communications. Here we present a chip scale optical parametric oscillator based on an…

Imaging applications in the terahertz (THz) frequency range are severely restricted by diffraction. Near-field scanning probe microscopy is commonly employed to enable mapping of the THz electromagnetic fields with sub-wavelength spatial…

In this work, a plasmonic right-angled waveguide bend and divider are proposed. Using the Transformation Optics (TO) approach the transformation media of a bend and a T-shaped divider are obtained. Such media with continuous refractive…

Optics · Physics 2021-04-07 Samaneh Pakniyat , Shahrokh Jam , Alireza Yahaghi , George W Hanson

In this paper, we study the sensitivity-tunable Terahertz (THz) liquid/gas biosensor in a coupling prism-three-dimensional Dirac semimetal (3D DSM) multilayer structure. The high sensitivity of the biosensor originates from the sharp…

Using terahertz time domain spectroscopy we demonstrate tunable polarization rotation and circular dichroism in intrinsically nonchiral planar terahertz metamaterials without twofold rotational symmetry. The observed effect is due to…

Optics · Physics 2010-09-03 Ranjan Singh , Eric Plum , Weili Zhang , Nikolay I. Zheludev

We propose an alternative explanation for the observed coherent down-conversion in a laser-enabled plasmonic photo-mixer involving infrared, millimeter-wave, microwave photons. We will offer a path toward full experimental characterization…

Optics · Physics 2025-08-06 Hamid Javadi

Terahertz (THz) waves are a highly sensitive probe of free carrier concentrations in semiconducting materials. However, most experiments operate in the far-field, which precludes the observation of nanoscale features that affect the…

In display technologies or data processing, planar and subwavelength free-space components suited for flat photonic devices are needed. Metasurfaces, which shape the optical wavefront within hundreds of nanometers, can provide a solution…

Graphene, owing to its ability to support plasmon polariton waves in the terahertz frequency range, enables the miniaturization of antennas to allow wireless communications among nanosystems. One of the main challenges in the demonstration…

All-dielectric optical metasurfaces can locally control the amplitude and phase of light at the nanoscale, enabling arbitrary wavefront shaping. However, lack of post-fabrication tunability has limited the true potential of metasurfaces for…

Active wavefront control in high-power laser illumination systems is important for technologies such as additive manufacturing, free-space laser communication, and power transmission. Conventional spatial light modulators (SLMs) and…

We propose and analyze the detector of modulated terahertz (THz) radiation based on the graphene field-effect transistor with mechanically floating gate made of graphene as well. The THz component of incoming radiation induces resonant…

Mesoscale and Nanoscale Physics · Physics 2015-06-19 D. Svintsov , V. G. Leiman , V. Ryzhii , T. Otsuji , M. S. Shur

THz radiation is more and more commonplace in research laboratories as well as in everyday life, with applications ranging from body scanners at airport security to short range wireless communications. In the optical domain, waveguides and…

Optics · Physics 2018-05-07 Alessio Stefani , Simon C. Fleming , Boris T. Kuhlmey

A new approach for the spatial and temporal modulation of electromagnetic fields at terahertz frequencies is presented. The waveguiding elements are based on plasmonic and metamaterial notions and consist of an easy-to-manufacture periodic…

Metasurfaces with tunable spatial phase functions could benefit numerous applications. Currently, most approaches to tuning rely on mechanical stretching which cannot control phase locally, or by modulating the refractive index to exploit…

Optics · Physics 2017-01-11 Shane Colburn , Alan Zhan , Arka Majumdar

Ultrafast manipulation of optical resonance can establish the time-boundary effect in time-variant media leading to a new degree of freedom for coherent control of electromagnetic waves. Here, we demonstrate that a free-standing all…

Topological Insulator-based devices can transport electrons/photons at the surfaces of materials without any back reflections, even in the presence of obstacles. Topological properties have recently been studied using non-reciprocal…

Optics · Physics 2016-11-03 Babak Bahari , Ricardo Tellez-Limon , Boubacar Kanté

We studied a metasurface constituted as a periodic array of semiconductor split-ring resonators. The resonance frequencies of the metasurface excited by normally incident light were found to be continuously tunable in the terahertz regime…

Materials Science · Physics 2009-05-02 Jiaguang Han , Akhlesh Lakhtakia , Cheng-Wei Qiu

As a key component for next-generation wireless communications (6G and beyond), terahertz (THz) electronic oscillators are being actively developed. Precise and dynamic phase control of ultrafast THz waveforms is essential for high-speed…

We theoretically consider infrared-driven hyperbolic metamaterials able to spatially filtering terahertz radiation. The metamaterial is a slab made of alternating semiconductor and dielectric layers whose homogenized uniaxial response, at…

Optics · Physics 2015-06-05 Carlo Rizza , Alessandro Ciattoni , Elisa Spinozzi , Lorenzo Columbo