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Related papers: Optimization of terahertz absorption in periodic q…

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We have performed ultrafast pump-probe experiments on a GaAs-AlAs microcavity with a resonance near 1300 nm in the "original" telecom band. We exploit the virtually instantaneous electronic Kerr effect to repeatedly and reproducibly switch…

Regular black holes (RBHs) -- geometries free from curvature singularities -- arise naturally in theories of non linear electrodynamics. Here we study the absorption, and superradiant amplification, of a monochromatic planar wave in a…

General Relativity and Quantum Cosmology · Physics 2024-01-04 Marco A. A. de Paula , Luiz C. S. Leite , Sam R. Dolan , Luís C. B. Crispino

We propose to use the energy absorption spectroscopy to measure the kinetic coefficients of unitary Fermi gases in a uniform potential. We show that in our scheme, the energy absorption spectrum is proportional to the dynamic structure…

Quantum Gases · Physics 2018-04-18 Pengfei Zhang , Zhenhua Yu

The acoustic properties of a porous sheet of medium resistivity backed by a rigid plate in which are embedded a periodic set of circular inclusions is investigated. Such a structure behaves like a multi-component diffraction gratings.…

Classical Physics · Physics 2010-07-20 Jean-Philippe Groby , Olivier Dazel , Aroune Duclos , Laurens Boeckx , Walter Lauriks

The photoluminescence (PL) spectra of a two-dimensional electron system induced in a Be-delta-doped GaAs/AlGaAs quantum well (QW) with a back gate are measured. The electron density is controlled from 1 X 10^{9} cm^{-2} to 2.5 X 10^{11}…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 M. Yamaguchi , S. Nomura , D. Sato , T. Akazaki , H. Tamura , H. Takayanagi

The influence of absorption on the spectra of microwave graphs has been studied experimentally. The microwave networks were made up of coaxial cables and T junctions. First, absorption was introduced by attaching a 50 Ohm load to an…

Chaotic Dynamics · Physics 2014-04-01 M. Allgaier , S. Gehler , S. Barkhofen , H. -J. Stöckmann , U. Kuhl

We investigate the impact of quantum well (QW) thickness on efficiency loss in c-plane InGaN/GaN LEDs using a small-signal electroluminescence (SSEL) technique. Multiple mechanisms related to efficiency loss are independently examined,…

The authors theoretically investigate quantum confinement and transition energies in quantum wells (QWs) asymmetrically positioned in wrinkled nanomembranes. Calculations reveal that the wrinkle profile induces both blue- and redshifts…

Mesoscale and Nanoscale Physics · Physics 2012-06-14 P. Cendula , S. Kiravittaya , O. G. Schmidt

Double-layer quantum Hall systems at Landau level filling factor $\nu=1$ have a broken symmetry ground state with spontaneous interlayer phase coherence and a gap between symmetric and antisymmetric subbands in the absence of interlayer…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Yogesh N. Joglekar , Allan H. MacDonald

We study spectral singularities and their application in determining the threshold gain coefficient $g^{(E/M)}$ for oblique transverse electric/magnetic (TE/TM) modes of an infinite planar slab of homogenous optically active material. We…

Quantum Physics · Physics 2015-06-23 Ali Mostafazadeh , Mustafa Sarisaman

Near perfect infrared light absorption at multi-spectral wavelengths has been experimentally demonstrated by using multiplexed metal square plasmon resonance structures. Optical power absorption over 95% has been observed in dual-band…

Optics · Physics 2015-06-12 Boyang Zhang , Joshua Hendrickson , Junpeng Guo

Atomically-resolved Z-contrast and strain mappings are used to extract a model of the composition of an InGaAs/InAlAs asymmetric coupled quantum-well structure grown on InP using metal-organic vapor phase epitaxy. The model accounts for…

We theoretically predict and experimentally demonstrate inhibition of linear absorption for phase and group velocity mismatched second and third harmonic generation in strongly absorbing materials, GaAs in particular, at frequencies above…

We consider the absorption of microwaves by a quantum Hall droplet. We show that the number and velocities of charged edge modes can be directly measured from a droplet of known shape. In contrast to standard transport measurements,…

Strongly Correlated Electrons · Physics 2013-10-30 Jennifer Cano , Andrew C. Doherty , Chetan Nayak , David J. Reilly

Communications in the terahertz band (THz) (0.1--10~THz) have been regarded as a promising technology for future 6G and beyond wireless systems, to overcome the challenges of evergrowing wireless data traffic and crowded spectrum. As the…

Information Theory · Computer Science 2022-05-26 Chong Han , Weijun Gao , Nan Yang , Josep M. Jornet

We demonstrate saturable absorber behavior of n-type semiconductors GaAs, GaP and Ge in THz frequency range at room temperature using nonlinear THz spectroscopy. The saturation mechanism is based on a decrease in electron conductivity of…

Other Condensed Matter · Physics 2015-05-18 Matthias C. Hoffmann , Dmitry Turchinovich

We measure the Hall conductivity of a two-dimensional electron gas formed at a GaAs/AlGaAs heterojunction in the terahertz regime close to the cyclotron resonance frequency by employing a highly sensitive Faraday rotation method coupled…

Mesoscale and Nanoscale Physics · Physics 2015-12-16 A. V. Stier , C. T. Ellis , H. Zhang , D. Eason , G. Strasser , B. D. McCombe T. Morimoto , H. Aoki , J. Cerne

Using optical technology for current injection and electromagnetic emission simplifies the comparison between materials. Here, we inject current into monolayer graphene and bulk gallium arsenide (GaAs) using two-color quantum interference…

In an absorptive system the Wigner reaction $K-$matrix (directly related to the impedance matrix in acoustic or electromagnetic wave scattering) is non-selfadjoint, hence its eigenvalues are complex. The most interesting regime arises when…

Disordered Systems and Neural Networks · Physics 2023-08-11 Yan V. Fyodorov

Within the framework of the single-particle approximation, the envelopes of the spectral lines of terahertz absorption and inelastic neutron scattering corresponding to magnetic dipole transitions between the sublevels of Tb$^{3+}$ ions in…

Strongly Correlated Electrons · Physics 2026-05-12 V. V. Klekovkina , B. Z. Malkin