Marcia Portella Oberli

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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 ...

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 ...

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 ...

Periodic photonic structures have attracted much interest due to their versatility for controlling light propagation. The dispersion of photon modes in photonic lattices exhibits an energy band structure analo-gous to the electronic one in crystals. An imp ...

We demonstrate that the interaction between excitons and a sea of incoherent electrons does not preclude excitons dressing by light. We investigate if exciton-electron scattering plays some inhibiting role in the coherent light-exciton coupling by measurin ...

Using femtosecond pump-probe spectroscopy, we identify excitation-induced dephasing as a major mechanism responsible for the breakdown of the strong coupling between excitons and photons in a semiconductor microcavity. The effects of dephasing are observed ...

We demonstrate the existence of a cross Feshbach resonance by strongly driving a lower polariton mode and by monitoring in time the transmission of a short optical pulse at the energy of the upper polariton mode in a semiconductor microcavity. From the sig ...

We investigate polariton-polariton interactions in a semiconductor microcavity through two-dimensional Fourier transform (2DFT) spectroscopy. We observe, in addition to the lower-lower and the upper-upper polariton self-interactions, a lower-upper cross in ...

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 spinor polariton interactions in GaAs based microcavities. This investigation is carried out by means of heterodyne polarized pump-probe spectroscopy. We show the dependence of the energy renormalization of the lower and upper polariton resona ...

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 ...

Using an angle-resolved heterodyne four-wave-mixing technique, we probe the low momentum excitation spectrum of a coherent polariton gas. The experimental results are well captured by the Bogoliubov transformation which describes the transition from single ...

Interactions among excitons, trions, and electrons are studied in CdTe modulation-doped quantum wells. These many-body interactions are investigated through the nonlinear dynamical properties in the excitonic complexes using time and spectrally resolved pump and probe techniques. This study is performed as a function of temperature and densities of excitons, trions, and electrons. The results reveal that the nonlinearities induced by trions differ from those induced by excitons and moreover they are mutuall

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 report on the nonlinear optical dynamical properties of excitonic complexes in CdTe modulation-doped quantum wells, due to many-body interactions among excitons, trions, and electrons. These were studied by time and spectrally resolved pump-probe experiments. The results reveal that the nonlinearities induced by trions differ from those induced by excitons, and in addition they are mutually correlated. We propose that the main source of these subtle differences comes from the Pauli exclusion-principle th

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 ...

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 ...

We report on the effect of noise on the characteristics of the bistable polariton emission system. The present experiment provides a time-resolved access to the polariton emission intensity. We evidence the noise-induced transitions between the two stable ...

We present an experimental signature of the Anderson localisation of microcavity polaritons, and provide a systematic study of the dependence on disorder strength. We reveal a controllable degree of localisation, as characterised by the inverse-participati ...

We present the results of a detailed time-resolved luminescence study carried out on a very high quality InGaAs quantum well sample where the contributions at the energy of the exciton and at the band edge can be clearly separated. We perform this experiment with a spectral resolution and a sensitivity of the setup, allowing us to keep the observation of these two separate contributions over a broad range of times and densities. This allows us to directly evidence the exciton formation time, which depends o

Marcia Portella Oberli

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Ultrafast tristable spin memory of a coherent polariton gas

Influence of a nonradiative reservoir on polariton spin multistability

Nonlinear relaxation and selective polychromatic lasing of confined polaritons

Localized Photon Lasing in a Polaritonic Lattice Landscape

Dressed excitons within an incoherent electron gas: Observation of a Mollow triplet and an Autler-Townes doublet

Dephasing effects on coherent exciton-polaritons and the breakdown of the strong coupling regime

Polaritonic Cross Feshbach Resonance

Two-dimensional Fourier transform spectroscopy of exciton-polaritons and their interactions

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

Heterodyne spectroscopy of polariton spinor interactions

Spinor stochastic resonance

From Single Particle to Superfluid Excitations in a Dissipative Polariton Gas

Many-body interaction evidenced through exciton-trion-electron correlated dynamics

Spatial dynamics of confined semiconductor microcavity polaritons

Interacting many-body systems in quantum wells: Evidence for exciton-trion-electron correlations

Spatial multistability induced by cross interactions of confined polariton modes

Intraband carrier photoexcitation in quantum dot lasers

Effect of a noisy driving field on a bistable polariton system

Anderson localisation in steady states of microcavity polaritons

Determination of the exciton formation in quantum wells from time-resolved interband luminescence