English
Related papers

Related papers: Electroabsorption in gated GaAs nanophotonic waveg…

200 papers

Aluminum gallium arsenide (AlGaAs) and related III-V semiconductors have excellent optoelectronic properties. They also possess strong material nonlinearity as well as high refractive indices. In view of these properties, AlGaAs is a…

In this article, we report the first observation of nanosecond laser induced transient dual absorption bands, one in the bandgap (TA1) and another in the sub-bandgap (TA2) regions of a-Ge5As30Se65 thin films. Strikingly, these bands are…

Materials Science · Physics 2015-09-25 Pritam Khan , Tarun Saxena , K. V. Adarsh

We investigate the nonlinear optical response of a commercial extended-wavelength In$_{0.81}$Ga$_{0.19}$As photodetector. Degenerate two-photon absorption in the mid-infrared range is observed at room temperature using a quantum cascade…

Superlattices are promising low-dimensional nanomaterials for thermoelectric technology that is capable of directly converting low-grade heat energy to useful electrical power. In this work, the thermal conductivities of GaAs/Ge…

Mesoscale and Nanoscale Physics · Physics 2017-06-28 Roger Jia , Lingping Zeng , Gang Chen , Eugene A. Fitzgerald

Tremendous scientific progress has been achieved through the development of nonlinear integrated photonics. Prominent examples are Kerr-frequency-comb generation in micro-resonators, and supercontinuum generation and frequency conversion in…

III V semiconductor nanowire based photodetectors have significant potential for remote sensing and LiDAR applications, particularly due to their ability to operate at 1.55 {\mu}m. Achieving room temperature operation and near unity…

The absorption coefficient for surface acoustic waves in a piezoelectric insulator in contact with a GaAs/AlGaAs heterostructure (with two-dimensional electron mobility $\mu= 1.3\times 10^5 cm^2/V\cdot s)$ at T=4.2K) via a small gap has…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 I. L. Drichko , A. M. Diakonov , A. M. Kreshchuk , T. A. Polyanskaya , I. G. Savel'ev , I. Yu. Smirnov , A. V. Suslov

We present an experimental method to determine the refractive index of $Al_{x}Ga_{1-x}As$ (x = 0.0 - 0.5) from 300 K to 4 K across the 500 - 1100 nm wavelength range. The values are extracted from spectroscopically observed microcavity…

Temperature dependence of intersubband transitions in AlN/GaN multiple quantum wells grown with molecular beam epitaxy is investigated both by absorption studies at different temperatures and modeling of conduction-band electrons. For the…

Engineering nanophotonic mode dispersions in ultrathin, planar structures enables significant control over infrared perfect absorption (PA) and thermal emission characteristics. Here, using simulations, the wavelength and angular ranges…

Optics · Physics 2022-01-14 Ben Johns , Shashwata Chattopadhyay , Joy Mitra

The heat transport in heavy-doped n-GaAs has been investigated at temperatures T=300 K and 77 K using the irradiation of the metal-semiconductor contact by modulated CO_{2}-laser radiation. It is shown this approach giving an opportunity to…

Materials Science · Physics 2007-05-23 A. Ya. Shul'man , N. A. Mordovets , I. N. Kotel'nikov

One of the basic optoelectronic characteristics is the absorption of any optoelectronic device or material. We present the characteristics of pure GaAs and the deviation of ideal spectra. Due to crystal defects, vacancies, impurities, etc.,…

Materials Science · Physics 2024-01-17 Subarna Alam , Mohammad Jahangir Alam

Photodetectors are typically based on photocurrent generation from electron-hole pairs in semiconductor structures and on bolometry for wavelengths that are below bandgap absorption. In both cases, resonant plasmonic and nanophotonic…

Mesoscale and Nanoscale Physics · Physics 2016-06-13 Kelly W. Mauser , Slobodan Mitrovic , Seyoon Kim , Dagny Fleischman , Harry A. Atwater

Franz-Keldysh effect is expressed in the smearing of the absorption edge in semiconductors under high electric fields. While Franz and Keldysh considered a limited case of externally applied uniform electric field, the same effect may be…

Applied Physics · Physics 2018-08-30 Yury Turkulets , Ilan Shalish

We present a low-loss integrated photonics platform in the visible and near ultraviolet regime. Fully-etched waveguides based on atomic layer deposition (ALD) of aluminum oxide operate in a single transverse mode with $<$3 dB/cm propagation…

We probe the electron transport properties in the shell of GaAs/In0.2Ga0.8As core/shell nanowires at high electric fields using optical pump / THz probe spectroscopy with broadband THz pulses and peak electric fields up to 0.6 MV/cm. The…

Mesoscale and Nanoscale Physics · Physics 2020-06-24 Rakesh Rana , Leila Balaghi , Ivan Fotev , Harald Schneider , Manfred Helm , Emmanouil Dimakis , Alexej Pashkin

Non-degenerate two-photon absorption (TPA) is investigated in a nanophotonic silicon waveguide in a configuration such that the dispersion of the nonlinear absorption and refraction cannot be neglected. It is shown that a signal wave can…

Optical characterization of AlGaAs microdisk resonant cavities with a quantum dot active region is presented. Direct passive measurement of the optical loss within AlGaAs microdisk resonant structures embedded with InAs/InGaAs…

The distributed absorption of photons in photodiodes induces an excess noise in continuous-wave photodetection above the transit-time roll-off frequency. We show that it can be treated as a frequency-dependent excess optical loss in…

Quantum Physics · Physics 2018-12-11 Takahiro Serikawa , Akira Furusawa

Enhancing the absorption and emission of electromagnetic waves over a broad range of wavelengths is a topic of fundamental and applied interest in photonics and energy research. In the context of light trapping in solar cells, for example,…

Optics · Physics 2018-12-27 Aaswath Raman , Zongfu Yu , Shanhui Fan