Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

physica status solidi (b)

Dynamics of Incoherent Excitonic Optical Nonlinearities in GaAs–GaAlAs MQWS's

K. Henneberger, Günter Manzke

Published Dec 1, 1988• 0 citations
Publisher

Abstract

Abstract The dynamics of optical nonlinearities connected with the blue‐shift of the exciton line in resonantly excited GaAs–GaAlAs MQWS's is investigated theoretically simulating a two‐beam experiment. Jumps in the optical spectra of a weak test pulse (optical switching), which follows the intense pump pulse at different time delays, are observed, basing on a strong increase of the absorption. A similar mechanism of the bistability is observed in connection with the electro‐absorptive effect.

DOI
10.1002/pssb.2221500255

Related papers

Nonlinear Propagation of Laser Pulses in GaAs‐GaAlAs MQWS

Günter Manzke, K. Henneberger

Abstract A theoretical approach is presented for the description of nonlinear optical properties of GaAs‐GaAlAs MQWS connected with the blue‐shift of the 1s‐exciton resonance at high excitation. An experimental situation is considered where the MQWS is resonantly excited by a pump pulse of narrow spectral width creating a high density of excitons, and where the optical spectra are recorded by an ultrafast broad‐band probe pulse at different time delays. The densities of excitons in the single GaAs wells are determined by the simultaneous solution of the exciton diffusion and the optical problem of wave propagation. With increasing pump intensity jumps of the exciton densities in certain layers appear when the maximum of absorption crosses the pump frequency due to the blue‐shift of the resonance. The mechanism of the corresponding bistabilities in the reflection and transmission spectra is similar to that observed in connection with the quantum‐confined Stark effect.

physica status solidi (b)•Jun 1, 1988•8 citations

Nonlinearities in the absorption and photoluminescence spectra of GaAs/AlAs type II heterostructures

Greg R. Olbright, W. S. Fu, J. F. Klem +5 more

We present here the first observation of quasisteady state optical nonlinearities in the absorption and photoluminescence (PL) spectra of GaAs/AlAs type II heterostructures. Using pump-probe spectroscopy we observed deep modulation, ΔT ~ 0.5 (Δα =−50,000 cm−1), due to a >40-meV blue shift and bleaching of the heavy hole exciton absorption peak. In addition, a blue shift of up to ~10 meV of the indirect PL line is observed with increasing PL excitation intensity. These nonlinearities are understood in terms of spatially separated layers of electrons and holes that are produced by the optical excitation process.

•May 21, 1990•0 citations

Nonlinear ligth propagation in GaAs-GaAlAs MQW's

K. Henneberger, Günter Manzke

The propagation of a laser pulse through a GaAs-GaAlAs MQW is investigated in the frame of classical optics. Optical spectra are calculated in the vicinity of the 1 s -exciton resonance of GaAs taking into account interference effects and nonlinear absorption caused by many-exciton effects at high excitation. The density of excited e-h pairs and intensities of transmitted and reflected beam are determined in dependence on the intensity of stationary incident laser beam by simultaneous solution of the problem of exciton diffusion and propagation of the electromagnetic wave. The observed strong nonlinearities refer to an optical bistable behaviour.

Physica Scripta•Oct 1, 1988•2 citations

Optical bistability in semiconductors

H. M. Gibbs, S. L. McCall, Thirumalai Venkatesan +3 more

Optical bistability has been observed in a semiconductor for the first time. The bistable etalon consists of a GaAlAs-GaAs-GaAlAs molecular-beam-epitaxially-grown sandwich with 90% reflectivity coatings. The bistability is primarily dispersive with the nonlinear refractive index arising from light-induced changes in exciton absorption. Using light of frequency just below the exciton peak, we observed bistability from 5 to 120 °K with 40-ns turn-off and subnanosecond turn-on times with 1 mW/μm2 holding intensity.

Applied Physics Letters•Sep 15, 1979•443 citations

Many body interactions and dynamic shift of the absorption resonance wavelength in all-optical polarization switching of InGaAs(P) MQWs

Tao Wang, An Li, Zheyuan Tan

Exciton saturation and optical nonlinearities in multiple quantum wells due to many body interactions consisting of phase-space filling and Coulomb screening are investigated. We have made a theoretical model to compare the different effects induced by the two many-body interactions. We focus our calculations on the shift of the exciton absorption resonance at highly excited carrier densities in MQW which can be obtained through femtosecond pump-probe technique. We find that the blue shift of the exciton absorption resonance wavelength caused by the phase-space filling effects is about equivalent to the red shift of Coulomb screening effects in same circular polarization, while in contrary the red shift is much lager than the blue shift in opposite circular polarization. This phenomenon happens within optical switching timescale.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Nov 29, 2007•13 citations

Subpicosecond excitonic optical nonlinearities in quantum wells

M. Joffre, Daniele Hulin, A. Migus +2 more

Excitonic resonances in semiconductors are very sensitive to applied optical fields. We present here a comparison between the effects of resonant and non resonant optical excitation, creating respectively real or virtual excitons. A blue shift of the exciton line and a reduction of the oscillator strength are simultaneously observed in multiple-quantum-well-structures for the two following cases : presence of a population of real excitons in very thin wells (two-dimensional systems), or presence of an intense offresonance non absorbed optical field (virtual excitons) independently of the well thickness. The latter configuration (optical Stark effect) has been studied as a function of pump intensity, determining in particular how the saturation of the blue shift is related to the exciton bleaching.

Revue de Physique Appliquée•Jan 1, 1987•8 citations
Abstract The dynamics of optical nonlinearities connected with the blue‐shift of the exciton line in resonantly excited GaAs–GaAlAs MQWS's is investigated theoretically simulating a two‐beam experiment. Jumps in the optical spectra of a weak test pulse (optical switching), which follows the intense pump pulse at different time delays, are observed, basing on a strong increase of the absorption. A similar mechanism of the bistability is observed in connection with the electro‐absorptive effect.
Abstract A theoretical approach is presented for the description of nonlinear optical properties of GaAs‐GaAlAs MQWS connected with the blue‐shift of the 1s‐exciton resonance at high excitation. An experimental situation is considered where the MQWS is resonantly excited by a pump pulse of narrow spectral width creating a high density of excitons, and where the optical spectra are recorded by an ultrafast broad‐band probe pulse at different time delays. The densities of excitons in the single GaAs wells are determined by the simultaneous solution of the exciton diffusion and the optical problem of wave propagation. With increasing pump intensity jumps of the exciton densities in certain layers appear when the maximum of absorption crosses the pump frequency due to the blue‐shift of the resonance. The mechanism of the corresponding bistabilities in the reflection and transmission spectra is similar to that observed in connection with the quantum‐confined Stark effect.
We present here the first observation of quasisteady state optical nonlinearities in the absorption and photoluminescence (PL) spectra of GaAs/AlAs type II heterostructures. Using pump-probe spectroscopy we observed deep modulation, ΔT ~ 0.5 (Δα =−50,000 cm−1), due to a >40-meV blue shift and bleaching of the heavy hole exciton absorption peak. In addition, a blue shift of up to ~10 meV of the indirect PL line is observed with increasing PL excitation intensity. These nonlinearities are understood in terms of spatially separated layers of electrons and holes that are produced by the optical excitation process.
The propagation of a laser pulse through a GaAs-GaAlAs MQW is investigated in the frame of classical optics. Optical spectra are calculated in the vicinity of the 1 s -exciton resonance of GaAs taking into account interference effects and nonlinear absorption caused by many-exciton effects at high excitation. The density of excited e-h pairs and intensities of transmitted and reflected beam are determined in dependence on the intensity of stationary incident laser beam by simultaneous solution of the problem of exciton diffusion and propagation of the electromagnetic wave. The observed strong nonlinearities refer to an optical bistable behaviour.
Optical bistability has been observed in a semiconductor for the first time. The bistable etalon consists of a GaAlAs-GaAs-GaAlAs molecular-beam-epitaxially-grown sandwich with 90% reflectivity coatings. The bistability is primarily dispersive with the nonlinear refractive index arising from light-induced changes in exciton absorption. Using light of frequency just below the exciton peak, we observed bistability from 5 to 120 °K with 40-ns turn-off and subnanosecond turn-on times with 1 mW/μm2 holding intensity.
Exciton saturation and optical nonlinearities in multiple quantum wells due to many body interactions consisting of phase-space filling and Coulomb screening are investigated. We have made a theoretical model to compare the different effects induced by the two many-body interactions. We focus our calculations on the shift of the exciton absorption resonance at highly excited carrier densities in MQW which can be obtained through femtosecond pump-probe technique. We find that the blue shift of the exciton absorption resonance wavelength caused by the phase-space filling effects is about equivalent to the red shift of Coulomb screening effects in same circular polarization, while in contrary the red shift is much lager than the blue shift in opposite circular polarization. This phenomenon happens within optical switching timescale.
Excitonic resonances in semiconductors are very sensitive to applied optical fields. We present here a comparison between the effects of resonant and non resonant optical excitation, creating respectively real or virtual excitons. A blue shift of the exciton line and a reduction of the oscillator strength are simultaneously observed in multiple-quantum-well-structures for the two following cases : presence of a population of real excitons in very thin wells (two-dimensional systems), or presence of an intense offresonance non absorbed optical field (virtual excitons) independently of the well thickness. The latter configuration (optical Stark effect) has been studied as a function of pump intensity, determining in particular how the saturation of the blue shift is related to the exciton bleaching.