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Related papers: Anisotropic excitonic photocurrent in $\beta$-Ga$_…

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We calculate the photocurrent in a clean graphene sample normally irradiated by a monochromatic electromagnetic field and subject to a step-like electrostatic potential. We consider the photon energies $\hbar\Omega$ that significantly…

Mesoscale and Nanoscale Physics · Physics 2011-02-04 S. Mai , S. V. Syzranov , K. B. Efetov

We study the microscopic origins of photocurrent generation in the topological insulator Bi$_2$Se$_3$ via time- and angle-resolved photoemission spectroscopy. We image the unoccupied band structure as it evolves following a circularly…

We investigated excitonic absorptions in GaAs/AlAs/GaAs single barrier heterostructure using both photocapacitance and photocurrent spectroscopies at room temperature. Photocapacitance spectra show well defined resonance peak of indirect…

Mesoscale and Nanoscale Physics · Physics 2018-02-02 Amit Bhunia , Mohit Kumar Singh , Y. Galvao Gobato , Mohamed Henini , Shouvik Datta

We show that a two-band model with ${\bf k}$-dependent superconducting gaps well describes the transmission and optical conductivity measured for MgB$_2$ thin films. It is also shown that the two-band anisotropic model consistently…

Superconductivity · Physics 2009-11-10 Takashi Yanagisawa , Hajime Shibata

We have observed a new optical transition in the photoreflectance spectra of indirect-gap BiOCl thin films, which were grown on SrTiO$_3$ substrates. The position of this transition is close in energy to its bulk critical point energy.…

Materials Science · Physics 2024-01-09 T. Nishiwaki , T. Makino , Z. Sun , D. Oka , T. Fukumura

Integrated polarimetric receivers have the potential to define a new generation of lightweight, high-performance instrumentation for remote sensing. To date, on-chip polarization-selective devices such as polarizing beam-splitters have yet…

Optics · Physics 2017-02-21 Jeff Chiles , Tracy Sjaardema , Ashutosh Rao , Sasan Fathpour

We employ polarization-shaped ultrafast optical pulses to generate photocurrents which only arise if the optically induced coherent polarization is frequency modulated. This frequency modulation is obtained via detuned excitation of…

Optics · Physics 2013-06-14 Shekhar Priyadarshi , Klaus Pierz , Mark Bieler

Bi2Se3 is a prototypical topological insulator which has a small band gap (~0.3 eV) and topologically protected conducting surface states. This material exhibits quite strong thermoelectric effects. Here we show in a mechanically exfoliated…

We investigated in detail the optical properties of several Cu(1-delta)Mg(delta)GeO3 (with delta=0,0.01), and CuGe(1-x)B(x)O3 with B=Si (x=0,0.007,0.05,0.1), and Al (x=0,0.01) single crystals, in the frequency range 20-32000 cm^-1. We…

Strongly Correlated Electrons · Physics 2009-10-31 A. Damascelli , D. van der Marel , G. Dhalenne , A. Revcolevschi

The results of photoconduction study of the Peierls conductors are reviewed. The studied materials are quasi-one-dimensional conductors with the charge-density wave: K$_{0.3}$MoO$_3$, both monoclinic and orthorhombic TaS$_3$ and also a…

Mesoscale and Nanoscale Physics · Physics 2014-12-16 S. V. Zaitsev-Zotov , V. F. Nasretdinova , V. E. Minakova

The quasi-static anisotropic permittivity parameters of electrically insulating gallium oxide (beta-Ga2O3) were determined by terahertz spectroscopy. Polarization-resolved frequency domain spectroscopy in the spectral range from 200 GHz to…

The relationship between the luminescence at 1.9 eV and the absorption bands at 2.0 eV and at 4.8 eV were investigated in a wide variety of synthetic silica samples exposed to different gamma- and beta-ray irradiation doses. We found that…

Materials Science · Physics 2007-05-23 L. Vaccaro , M. Cannas , B. Boizot

The photon-electron interactions are generally volatile and the intricate multiphysics details of photoexcited carrier dynamics are not yet distinguished. How to nonvolatile control the physical state through all-optical means and clarify…

Optics · Physics 2024-05-02 Zhen Lei , Jiawei Chang , Qiyi Zhao , Jian Zhou , Yuanyuan Huang , Qihua Xiong , Xinlong Xu

This work reports comprehensive theoretical modeling of photocurrent spectra generated by an In$_{0.91}$Ga$_{0.09}$N/In$_{0.4}$Ga$_{0.6}$N disk-in-wire photodiode. The strain distribution is calculated by valence-force-field (VFF) model,…

Mesoscale and Nanoscale Physics · Physics 2021-05-13 Fu-Chen Hsiao , Arnab Hazari , Pallab Bhattacharya , Yia-Chung Chang , John M. Dallesasse

The Li2SiO3 compound, a ternary electrolyte compound of Lithium-ion based batteries, exhibits unique geometric and band structures, an atom-dominated energy spectrum, charge densities distributions, atom and orbital-projected density of…

Materials Science · Physics 2020-10-23 Nguyen Thi Han , Vo Khuong Dien , Ming-Fa Lin

An excitonic insulator (EI) phase is a consequence of collective many-body effects where an optical band gap is formed by the condensation of electron-hole pairs or excitons. We report pressure-dependent optical pump optical probe…

Materials Science · Physics 2024-11-28 Vikas Arora , Victor S Muthu , Arijit Sinha , Luminita Harnagea , U V Waghmare , A K Sood

We present an investigation into the role of anode grid pitch and excitation spectrum on the performance of high-power optoelectronic switches utilizing Fe-doped $\beta$-Ga$_2$O$3$. By systematically varying the anode grid pitch ($20-80\…

Applied Physics · Physics 2025-12-17 Vikash Jangir , Sourojit K. Mazumder , Sudip K. Mazumder

Spectra of the degenerate two-photon absorption coefficient $\beta(\omega)$, anisotropy parameter $\sigma(\omega)$, and dichroism parameter $\delta(\omega) = \big[\sigma(\omega) + 2\eta(\omega)\big]/2$ of crystalline 110-cut GaAs, GaP, and…

Cross-polarized absorption peaks of isolated single-walled carbon nanotubes were observed by a polarized photoluminescence excitation (PLE) spectroscopy. Using a simple theory for PL anisotropy, the observed PLE spectra are decomposed into…

Materials Science · Physics 2009-11-11 Yuhei Miyauchi , Mototeru Oba , Shigeo Maruyama

Photoconduction in the monoclinic phase of quasi-one-dimensional conductor TaS$_3$ has been observed at $T < 70$~K. It was studied jointly with low-temperature ohmic and non-linear dark conduction. The strong sample quality dependence of…

Strongly Correlated Electrons · Physics 2014-12-16 V. E. Minakova , V. F. Nasretdinova , S. V. Zaitsev-Zotov