François Morier-Genoud

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Non-linear interactions in coherent gases are not only at the origin of bright and dark solitons and superfluids; they also give rise to phenomena such as multistability, which hold great promise for the development of advanced photonic and spintronic devi ...

We demonstrate three-dimensional spatial confinement of exciton-polaritons in a semiconductor microcavity. Polaritons are confined within a micron-sized region of slightly larger cavity thickness, called mesa, through lateral trapping of their photon compo ...

In this work, we study the influence of the excitation conditions on power-dependent spin switching and spin multistability of exciton polaritons in planar semiconductor microcavities. We obtain experimental evidence for the influence of a reservoir of non ...

Quantized vortices appear in quantum gases at the breakdown of superfluidity. In liquid helium and cold atomic gases, they have been indentified as the quantum counterpart of turbulence in classical fluids. In the solid state, composite light-matter bosons known as exciton polaritons have enabled studies of non-equilibrium quantum gases and superfluidity. However, there has been no experimental evidence of hydrodynamic nucleation of polariton vortices so far. Here we report the experimental study of a polar

Polaritons have often been proposed as promising candidates for the realization of all-optical devices due to the easy manipulation and control of their density and spin. In this paper we present a relaxation mechanism for confined polaritons and its appli ...

We optically excited the eigenmodes of an elliptic resonator in a semiconductor microcavity. Using a pulsed excitation, we created a superposition of eigenmodes, and imaged the temporal evolution of the coherent emission pattern. A semiconductor quantum we ...

We develop an analytical approximate method for determining the Bohr radii of Wannier-Mott excitons in thin quantum wells under the influence of magnetic field perpendicular to the quantum well plane. Our hybrid variational-perturbative method allows us to ...

We experimentally investigate the relaxation of spatially confined microcavity polaritons. We measure the time- and energy-resolved photoluminescence under resonant excitation and in the low-density regime. In this way, we have access to the time evolution ...

Coherent manipulation of spin ensembles is a key issue in the development of spintronics. In particular, multivalued spin switching may lead to new schemes of logic gating and memories. This phenomenon has been studied with atom vapours 30 years ago, but is still awaited in the solid state. Here, we demonstrate spin multistability with microcavity polaritons in a trap. Owing to the spinor nature of these light-matter quasiparticles and to the anisotropy of their interactions, we can optically control the sp

We present the optical tomography of the probability density of microcavity polaritons, confined in three dimensions by cylindrical traps of various sizes. Collecting the photoluminescence emitted by the quasimodes under continuous nonresonant laser excita ...

GaAs/AlxGa1-xAs multiple-quantum-well structures with identical well thicknesses (almost-equal-to 119 angstrom) but with different Al contents x in the barrier (x almost-equal-to 0. 1, 0.2, 0.45, and 1) were grown by molecular-beam epitaxy. We report the characterization of the structures by a combination of different techniques. The x-ray-diffraction technique allows us to estimate the Al content x and to measure the period of the structure with good accuracy. Using the photographs given by high-resolution

Control of the wave function of confined microcavity polaritons is demonstrated experimentally and theoretically by means of tailored resonant optical excitation. Three dimensional confinement is achieved by etching mesas on top of the microcavity spacer l ...

We report on noise-induced spin ordering in a collective quasiparticle system: spinor stochastic resonance. Synergetic interplay of a polarization-modulated signal and a polarization noise allows us to switch coherently between the two metastable states of ...

We resonantly excite exciton-polariton states confined in cylindrical traps. Using a homodyne detection setup, we are able to image the phase and amplitude of the confined polariton states. We evidence the excitation of vortex states, carrying an integer a ...

We report thermally stable latched operation of a nonlinear Fabry-Perot device without heat sinking other than through the 0.5-mm GaAs substrate. The device has a 2-μm GaAs spacer and integrated dielectric mirrors with reflectivities of 91% and 99%. Operated in reflection at a wavelength of 886 nm, thresholds as low as 1 mW, and contrast ratios of 10:1 have been observed. Measurements of the threshold dependence on the size of the excited spot give evidence for carrier diffusion and light-diffraction effect

We study the emission properties of confined polariton states in shallow zero-dimensional traps under nonresonant excitation. We evidence several relaxation regimes. For slightly negative photon-exciton detuning, we observe a nonlinear increase of the emis ...

We report on the dynamics of confined zero-dimensional polaritons. We excite resonantly discrete polariton states optically with a tailored picosecond laser pulse and observe their emission time resolved in the two-dimensional k space or real space. We are ...

We study the wave functions of exciton polaritons trapped in the elliptical traps of a patterned microcavity. A homodyne detection setup with numerical off-axis filtering allows us to retrieve the amplitude and the phase of the wave functions. Doublet stat ...

The cathodoluminescence mode of the scanning electron microscope is used for the first time to investigate the lateral dependence of the electron-hole pair generation by the electron beam of the scanning electron microscope m semiconducting material. A multiple-quantum-well structure acts as a detector to measure the relative number of generated carriers by their radiative recombination. The method, which avoids the effect of carrier diffusion, enhances the resolution of the measurement to 50 nm and should

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 ...

François Morier-Genoud

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Ultrafast tristable spin memory of a coherent polariton gas

Engineering the spatial confinement of exciton polaritons in semiconductors

Influence of a nonradiative reservoir on polariton spin multistability

Hydrodynamic nucleation of quantized vortex pairs in a polariton quantum fluid

Nonlinear relaxation and selective polychromatic lasing of confined polaritons

Coherent oscillations between orbital angular momentum polariton states in an elliptic resonator

Analytical method for determining quantum well exciton properties in a magnetic field

Enhancement of microcavity polariton relaxation under confinement

Multistability of a coherent spin ensemble in a semiconductor microcavity

Probability density tomography of microcavity polaritons confined in cylindrical traps of various sizes

Influence of Al Content in the Barrier on the Optical-Properties of Gaas/Alxga1-Xas(X=0.1-1) Multiple-Quantum-Well Structures

Coherent optical control of the wave function of zero dimensional exciton polaritons

Spinor stochastic resonance

Selective photoexcitation of confined exciton-polariton vortices

Thermally Stable Operation of a Bistable Fabry-Perot Etalon with a Bulk Gaas Spacer

Nonlinear relaxation of zero-dimension-trapped microcavity polaritons

Spatial dynamics of confined semiconductor microcavity polaritons

Phase-resolved imaging of confined exciton-polariton wave functions in elliptical traps

Determination of the Lateral Distribution of Electron-Hole Pairs Generated by an Electron-Beam in Al0.4Ga0.6As by Cathodoluminescence

Spatial multistability induced by cross interactions of confined polariton modes