Benoît Marie Joseph Deveaud

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We report on the observation of multiple polariton modes, originating from an electronic coupling between quantum wells inside a planar microcavity. A series of excitonic transitions are measured for a bare quantum well stack and are precisely identified t ...

An investigation of the parametric amplification and its coherent control in a semiconductor micro-cavity is presented. The time and angle resolved pump and probe experiments show that several ps after pumping parametric scattering is still phase coherent. The experimental data are in qualitative agreement with the numerical data obtained from a relatively simple theoretical model based on three polarisation components, pump, probe, and idler. This model also predicts that under particular circumstances, th

The coexistence of localized and free holes in modulation doped InGaAs/InP quantum wells, which show Fermi edge singularities in the cw photoluminescence and excitation spectra, has been determined by picosecond time-resolved luminescence spectroscopy. A long-lived peak at the tow-energy side of the emission spectrum is observed at 5 K and weak excitation. The peak, which vanishes on either increasing the temperature at similar to 30 K or increasing the excitation density, is attributed to recombination of

We report on time-resolved and steady-state photoluminescence studies of GaAs/AlGaAs V-groove quantum wire structures. Steady-state photoluminescence experiments are performed in the temperature range from 8 to 200 It. We evaluate the relation between photoluminescence excitation and absorption and determine experimentally the optical density in order to analyze the temperature dependence of the photoluminescence spectra. We find that, at a temperature above 60 K, the photoexcited electron-hole pairs reach

By means of an electron hole rate equation model we explain the phase dynamics of a quantum dot semiconductor optical amplifier and the appearance of different decay times observed in pump and probe experiments. The ultrafast hole relaxation leads to a fir ...

In the present work, we theoretically investigate the intersubband relaxation of electrons in quantum well systems during photoexcitation using an ensemble Monte Carlo approach. In particular, we compare with recent experimental results by Hartig et al. (Phys. Rev. B (1999)), in which time-resolved photoluminescence measurements are made of the second subband carrier population after band-to-band excitation in a wide coupled quantum well system. In these experiments, the first excited subband energy is less

One of the most striking quantum effects in an interacting Bose gas at low temperature is superfluidity. First observed in liquid 4He, this phenomenon has been intensively studied in a variety of systems for its remarkable features such as the persistence ...

An optical device for amplifying or emitting an optical beam of given wavelength comprises an optical source (20) in combination with a primary optical device (10) which is a semiconductor optical amplifier (SOA), a gain-clamped semiconductor optical ampli ...

We analyze the magnitude of degenerate two-photon gain of several quantum wells (QWs) in a resonant microcavity which is pumped off-resonantly by an optical field. A set of coupled phenomenological rate equations for electron-hole pairs and photons is derived. In the framework of this model, we make a realistic prediction of the time-integrated two-photon gain and find that a lambda-cavity containing 11 QWs would give a maximal amplification of similar to 2.3% for a peak,intensity of similar to 80 MW/cm(2).

We demonstrate the occurrence of spatial multistability using laterally confined microcavity exciton-polaritons. By coherently exciting with a blue detuned laser a series of confined polariton modes, we investigate the effects of multistability on the tran ...

The dynamics of intersubband relaxation in GaAs quantum wells and the role of hot carriers and the phonon distributions have been investigated using two different optical techniques with femtosecond resolution: 1) time-resolved photoluminescence and 2) pump and probe experiments. The (2-->1) intersubband relaxation times have been measured as functions of well widths (100 Angstrom < L(well) < 220 Angstrom), under different experimental conditions (15K < T-lattice < 300K, and 1x10(10) cm(-2) < excitation den

We unveil the role of bound-to-continuum photoexcitation of carriers as a relevant process that affects the performance of quantum dot (OD) lasers. We present the response of an InAs/InGaAs QD laser to a sub-band gap pump, showing an unexpected depletion o ...

Pump and probe measurements with femtosecond resolution are performed on a gain-clamped semiconductor optical amplifier, a structure that contains a lasing mode. The corresponding relaxation oscillations are observed in the temporal gain recovery of the amplifier. The current dependence of the oscillations is well reproduced by a small-signal analysis of the laser rate equations. The gain recovery can be very fast, we measure damping rates of up to 40 GHz.

We have grown high-electron mobility transistor structures in the Al0.3Ga0.7As/In0.25Ga0.75As/GaAs material system with In0.25Ga0.75As channel thicknesses in the range 40-200 Angstrom. We have monitored the onset of channel relaxation using Hall mobility measurements, polychromatic cathodoluminescence mapping, time-resolved photoluminescence, transmission electron microscopy, low-frequency noise,and deep-level transient spectroscopy measurements. It appears that the first relaxation symptom, the Stransky-Kr

We present a novel semiconductor structure in which 0D polaritons coexist with 2D microcavity polaritons. Spatial trapping of the 2D microcavity polaritons results from the confinement of their photonic part in a potential well, consisting of an adjustable ...

In this experimental work, we optically excite the eigenmodes of an elliptical resonator in a semiconductor micro-cavity. Using a pulsed excitation, we create a superposition of eigenmodes, and image the time evolution of the coherent emission pattern. Oscillations between vortex and anti-vortex states are observed, and remarkably well described within the Poincar sphere representation for an eigenmode containing an orbital angular momentum. A semiconductor quantum well is embedded in the microcavity struct

Advantages and remaining issues of state-of-the-art m-plane freestanding GaN (FS-GaN) substrates grown by halide vapor phase epitaxy (HVPE) for m-plane InGaN epitaxial film growth by metalorganic vapor phase epitaxy are described. Because of the low threading dislocation and basal-plane stacking fault densities, improved quantum efficiency and short radiative lifetime are achieved for the near-band-edge emission of 200–250 nm thick m-plane pseudomorphic InGaN epilayers. As the surface flatness is greatly im

In a pump-probe experiment, we have been able to control, with phase-locked probe pulses, the ultrafast nonlinear optical emission of a semiconductor microcavity, arising from polariton parametric amplification. This evidences the coherence of the polariton population near k = 0, even for delays much longer than the pulse width. The control of a large population at k = 0 is possible although the probe pulses are much weaker than the large polarization they control. With rising pump power the dynamics of the

Exciton-polariton condensation can be regarded as a self-organization phenomenon, where phase ordering is established among particles in the system. In such condensed systems, further ordering can occur in the particle density distribution, under particula ...

We have investigated the intersubband scattering of electrons in GaAs quantum wells using luminescence up-conversion with 100-fs resolution. The decay time of the n=2 electron-to-heavy-hole transition (e,hh)(2) depends both on the excess energy of the charge carriers and on the excitation density. A Monte Carlo simulation allows us to reproduce the experimental data with high accuracy. The intrinsic LO-phonon scattering rate is found to be 2.0x10(12) s(-1) for 80-meV subband separation. We show the wave-vec

Benoît Marie Joseph Deveaud

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Multiple polariton modes originating from the coupling of quantum wells in planar microcavity

Quantum kinetics of parametric polariton scattering in microcavities

Role of hole localization in the optical singularities of a two-dimensional electron gas studied by time-resolved photoluminescence

Photoluminescence study of V-groove quantum wires: The influence of disorder on the optical spectra and the carrier thermalization

Modeling of gain and phase dynamics in quantum dot amplifiers

Effect of intercarrier scattering on intersubband transitions in GaAs/AlGaAs quantum well systems

Quantized Vortices in an Exciton-Polariton Condensate

An integrated holding-beam-at-transparency (hbat) configuration for semiconductor optical amplification or emission

Feasibility study for degenerate-two-photon gain in a semiconductor microcavity

Spatial multistability induced by cross interactions of confined polariton modes

Ultrafast Dynamics of Intersubband Relaxation in Gaas Quantum-Wells - Hot-Carrier and Phonon Populations Effects

Intraband carrier photoexcitation in quantum dot lasers

Time-resolved relaxation oscillations in gain-clamped semiconductor optical amplifiers by pump and probe measurements

Optimum channel thickness of Al0.3Ga0.7As/In0.25Ga0.75As/GaAs heterostructures for electron transport applications

Zero dimensional exciton-polaritons

Coherent oscillations between polariton vortex and anti-vortex states in an elliptical resonator

Advantages and remaining issues of state-of-the-art m-plane freestanding GaN substrates grown by halide vapor phase epitaxy for m-plane InGaN epitaxial growth

Coherent control of polariton parametric scattering in semiconductor microcavities

Spontaneous Pattern Formation in a Polariton Condensate

Femtosecond luminescence measurements of the intersubband scattering rate in AlxGa1-xAs/GaAs quantum wells under selective excitation