Publications de Vincenzo Savona

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We adopt a kinetic theory of polariton non-equilibrium Bose-Einstein condensation, to describe the formation of off-diagonal long-range order. The theory accounts properly for the dominant role of quantum fluctuations in the condensate. In realistic situations with optical excitation at high energy, it predicts a significant depletion of the condensate caused by long-wavelength fluctuations. As a consequence, the one-body density matrix in space displays a partially suppressed long-range order and a pronoun

We investigate the occurrence of a phase transition, characterized by the spontaneous breaking of a discrete symmetry, in a driven-dissipative Bose-Hubbard lattice in the presence of two-photon coherent driving. The driving term does not lift the original ...

The exciton-polariton states of quantum wells embedded in planar semiconductor microcavities are usually described by assuming in-plane wave vector conservation. In this work we consider the two main k(parallel to)-scattering mechanisms, namely the polariton-phonon scattering and the in-plane structural disorder of the quantum well. We calculate the homogeneous and inhomogeneous broadening of the polariton levels and show that a detailed model of the scattering processes is essential for a theoretical deriv

We have measured the ultrafast resonant Rayleigh scattering from quantum-well excitons using Fourier-transform spectral interferometry. The experiment simultaneously measures a statistically significant number of speckles with 100 fs temporal resolution. We show that theories based on ensemble averaging can he compared directly with the experimental resonant Rayleigh scattering dynamics.

We develop a model of the collective excitation kinetics in the non-equilibrium polariton condensation. The model accounts for mutual interaction and for energy relaxation processes and predicts the effect of quantum fluctuations. In realistic situations with incoherent optical excitation, we find a significant depletion of the condensate caused by long-wavelength fluctuations. As a consequence, the spatial correlation function displays a partially suppressed long-range order.

We use the truncated Wigner approximation to derive stochastic classical field equations for the description of polariton condensates. Our equations are shown to reduce to the Boltzmann equation in the limit of low polariton density. Monte Carlo simulation ...

We study the quantum phase transition of the 1D weakly interacting Bose gas in the presence of disorder. We characterize the phase transition as a function of disorder and interaction strengths, by inspecting the long-range behavior of the one-body density ...

The problem of the density-dependent homogeneous broadening of microcavity polaritons due to exciton-exciton Coulomb interaction is addressed using the self-consistent Born approximation. The theoretical results predict that, for resonant pumping of the lower polariton, the dependence of its broadening on the density of excitations has a threshold behavior. Below the threshold density, scattering is strongly inhibited because it involves only the small region of k space where the polariton effective mass is

We investigate the behavior of two coupled nonlinear photonic cavities, in the presence of inhomogeneous coherent driving and local dissipations. By solving numerically the quantum master equation, either by diagonalizing the Liouvillian superoperator or b ...

We study a driven-dissipative array of coupled nonlinear optical resonators by numerically solving the von Neumann equation for the density matrix. We demonstrate that quantum correlated states of many photons can also be generated in the limit where the n ...

We address the problem of the photoluminescence of a quantum (QD) dot in a nanocavity, with focus on the case of nonzero detuning. In this regime, experiments have shown that strong emission from the cavity-like peak is still present for dot-cavity detunin ...

We study the coherence and density modulation of a nonequilibrium exciton-polariton condensate in a one-dimensional valley with disorder. By means of interferometric measurements we evidence a modulation of the ﬁrst-order coherence function and we relate i ...

We present a theoretical model of the time-resolved excitonic photoluminescence in quantum wires. We study the role of disorder on the temperature dependence of the photoluminescence lifetime. We find that at low temperature the exciton population is not thermalized in disordered quantum wires and that the lifetime is mainly determined by the localization length of the exciton. However for large localization lengths or high enough temperatures the exciton population thermalizes within its lifetime and the t

The ability of using integrated photonics to scale multiple optical components on a single monolithic chip offers key advantages to create miniature light-controlling chips. Numerous scaled optical components have been already demonstrated. However, presen ...

We study the one-dimensional Bose gas in spatially correlated disorder at zero temperature, using an extended density-phase Bogoliubov method. We analyze, in particular, the decay of the one-body density matrix and the behavior of the Bogoliubov excitation ...

Dissipative Kerr solitons arising from parametric gain in ring microresonators are usually described within a classical mean-field framework. Here, we develop a quantum-mechanical model of dissipative Kerr solitons in terms of the Lindblad master equation ...

Polaritons in confined systems are introduced and their dispersion is calculated. The amount of squeezing of confined excitons polaritons in GaAs quantum wells is evaluated.

We consider a nonequilibrium system of interacting emitters described by the XXZ model, whose excitonic transitions are spatially and spectrally coupled to a single mode cavity. We demonstrate that the output radiation field is sensitive to an interplay be ...

We present an experiment that probes polariton quantum correlations by exploiting quantum complementarity. Specifically, we find that polaritons in two distinct idler modes interfere if and only if they share the same signal mode so that "which-way" inform ...

We fabricate and experimentally characterize an H0 photonic crystal slab nanocavity with a design optimized for maximal quality factor, Q = 1.7 x 10(6). The cavity, fabricated from a silicon slab, has a resonant mode at lambda = 1.59 mu m and a measured Q- ...

Vincenzo Savona

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Kinetics of the Bose-Einstein condensation of microcavity polaritons

Spontaneous symmetry breaking in a quadratically driven nonlinear photonic lattice

Microcavity polaritons: Homogeneous and inhomogeneous broadening in the strong coupling regime

Speckle-averaged resonant Rayleigh scattering from quantum-well excitons

Kinetics of quantum fluctuations in polariton Bose Einstein condensation

Stochastic classical field model for polariton condensates

Mean-field phase diagram of the one-dimensional Bose gas in a disorder potential

Threshold behavior in the collision broadening of microcavity polaritons

Dissipative time crystal in an asymmetric nonlinear photonic dimer

Multimode entanglement in coupled cavity arrays

Monte Carlo model for the photoluminescence kinetics of a quantum dot embedded in a nanocavity

Polariton Condensation in a One-Dimensional Disordered Potential

Temperature dependence of the photoluminescence lifetime in disordered quantum wires

Ultra-wide-band structural slow light

Superfluid to Bose-Glass Transition in a 1D Weakly Interacting Bose Gas

Quantum dynamics of dissipative Kerr solitons

Polaritons In Confined Systems

Laser from a many-body correlated medium

Quantum complementarity of microcavity polaritons

High-Q silicon photonic crystal cavity for enhanced optical nonlinearities