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

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

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

Published Nov 29, 2007• 13 citations
Publisher

Abstract

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.

DOI
10.1117/12.755712

Related papers

The mechanism investigation of ultrafast all-optical switch based on electron spin polarization relaxation at 1.55μm

Tao Wang, An Li

Exciton saturation and optical nonlinearities caused by phase-space filling(PSF) in InGaAs(P) MQWs are investigated. In-well carrier population under pump beam is calculated as a function of time. Changes in absorption of the two circularly polarized component of the linear polarized test beam resulting from PSF are calculated by the semiconductor nonlinear absorption formula, respectively. The refractive indices of the two circularly polarized component are obtained from the K-K relations. Transient rotation angle of the major axis of the probe polarization is then deduced.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Nov 24, 2005•0 citations

Transient Rotation Angle in All-Optical Polarization Switching Based on InGaAs/InP MQWs

Tao Wang

An all-optical switch based on InGaAs/InP MQWs is investigated.Exciton saturation and optical nonlinearities caused by phase-space filling (PSF) in MQWs are discussed.In-well carrier population under pump beam is calculated as a function of time.The transient rotation angle of the major axis of the probe polarization is finally deduced from the K K relations. The results show that the maximum rotation angle of our optical switch reaches 60° when pump energy is at 100 pJ per fs pulse.

Optics & Optoelectronic Technology•Jan 1, 2006•0 citations

The excitonic Stark effect: absorption splitting and the influence of the light-hole exciton

Sangam Chatterjee, Peter Brick, Claudia Ell +5 more

Summary form only given. Since the original discovery of the excitonic optical Stark effect, substantial progress has been made in the understanding of this ultrafast nonlinear optical effect. Recently, a red shift of the excitonic absorption line has been reported using low intensity excitation detuned 4.5 meV below the 1s-heavy-hole (hh) resonance and cross-circularly-polarized pulses. This was attributed to higher-order Coulomb correlations, interpretable as bound and unbound two-exciton states and memory effects. For co-circularly polarized pulses the well-known blue shift was found. Here we present a related effect occurring in the higher-intensity regime. Standard pump-probe experiments were performed on high-quality 8.5 nm-thick In/sub 0.04/Ga/sub 0.96/As multiple quantum well (MQW) samples.

Quantum Electronics and Laser Science Conference•Nov 13, 2002•0 citations

Nonlinear absorption and refraction in strained InGaAs/InP multiple quantum wells for all-optical switching

P J Bradley, Riccardo A. Calvani, Domenico Campi +2 more

Absorption spectra of strained InGaAs/InP quantum wells exhibit a single, unusually large exciton feature. 60% quenching is obtained for 4.3 mW Nd:YAG effective pump power at a wavelength of 1.064 mu m. A simple two-level formula fits well the behaviour at the exciton peak, and absorption spectra are reasonably approximated by a standard two-dimensional exciton model. Saturation intensities calculated with these techniques range around 200 W cm-2. Finally the Kramers-Kronig relations are used to calculate the associated refractive index change.

Semiconductor Science and Technology•Apr 1, 1992•10 citations

Many-particle theory of all-optical polarization switching in semiconductor quantum wells

I. Rumyantsev, N. H. Kwong, Rolf H. Binder +2 more

Semiconductor quantum wells exhibit numerous nonlinear optical effects that are potentially useful in electro-optical or all-optical devices. In general, the underlying physical mechanisms are complex many-particle processes and can be viewed as interesting research subjects in their own right. One example of such a device is the all-optical polarization switch that has been demonstrated [1]. In that device, conventional (i.e. non-strained) GaAs quantum wells are used in conjunction with two polarizers to switch the throughput of a weak probe pulse with a strong pump pulse. The switching is due to an effective polarization rotation of the probe light by the pump light. The basic idea underlying this effective polarization rotation can be based on a simplified picture of two spin-degenerate heavy-hole exciton transitions. A linearly polarized probe pulse, which consists of right ("+") and left ("-") circularly polarized components, would not undergo polarization rotation, because it couples to both transitions in the same way. If, however, a circularly polarized pump beam modifies, for example, the transition frequency of the "+" transition, the absorption of the "+" component of the probe light differs from that of the "-" component. This leads to an effective polarization rotation.

Frontiers in Optics•Jan 1, 2003•0 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
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.
Exciton saturation and optical nonlinearities caused by phase-space filling(PSF) in InGaAs(P) MQWs are investigated. In-well carrier population under pump beam is calculated as a function of time. Changes in absorption of the two circularly polarized component of the linear polarized test beam resulting from PSF are calculated by the semiconductor nonlinear absorption formula, respectively. The refractive indices of the two circularly polarized component are obtained from the K-K relations. Transient rotation angle of the major axis of the probe polarization is then deduced.
Summary form only given. Since the original discovery of the excitonic optical Stark effect, substantial progress has been made in the understanding of this ultrafast nonlinear optical effect. Recently, a red shift of the excitonic absorption line has been reported using low intensity excitation detuned 4.5 meV below the 1s-heavy-hole (hh) resonance and cross-circularly-polarized pulses. This was attributed to higher-order Coulomb correlations, interpretable as bound and unbound two-exciton states and memory effects. For co-circularly polarized pulses the well-known blue shift was found. Here we present a related effect occurring in the higher-intensity regime. Standard pump-probe experiments were performed on high-quality 8.5 nm-thick In/sub 0.04/Ga/sub 0.96/As multiple quantum well (MQW) samples.
Absorption spectra of strained InGaAs/InP quantum wells exhibit a single, unusually large exciton feature. 60% quenching is obtained for 4.3 mW Nd:YAG effective pump power at a wavelength of 1.064 mu m. A simple two-level formula fits well the behaviour at the exciton peak, and absorption spectra are reasonably approximated by a standard two-dimensional exciton model. Saturation intensities calculated with these techniques range around 200 W cm-2. Finally the Kramers-Kronig relations are used to calculate the associated refractive index change.
Semiconductor quantum wells exhibit numerous nonlinear optical effects that are potentially useful in electro-optical or all-optical devices. In general, the underlying physical mechanisms are complex many-particle processes and can be viewed as interesting research subjects in their own right. One example of such a device is the all-optical polarization switch that has been demonstrated [1]. In that device, conventional (i.e. non-strained) GaAs quantum wells are used in conjunction with two polarizers to switch the throughput of a weak probe pulse with a strong pump pulse. The switching is due to an effective polarization rotation of the probe light by the pump light. The basic idea underlying this effective polarization rotation can be based on a simplified picture of two spin-degenerate heavy-hole exciton transitions. A linearly polarized probe pulse, which consists of right ("+") and left ("-") circularly polarized components, would not undergo polarization rotation, because it couples to both transitions in the same way. If, however, a circularly polarized pump beam modifies, for example, the transition frequency of the "+" transition, the absorption of the "+" component of the probe light differs from that of the "-" component. This leads to an effective polarization rotation.
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.