Publications associées à Second-order time correlations within a polariton Bose-Einstein condensate in a CdTe microcavity

Correlation properties of a one-dimensional repulsive Bose gas at finite temperature

We present a comprehensive study shedding light on how thermal fluctuations affect correlations in a Bose gas with contact repulsive interactions in one spatial dimension. The pair correlation function, the static structure factor, and the one-body density ...

IOP Publishing Ltd2023

Interaction of Confined Polaritons in Microcavity Structures

Morteza Navadeh Toupchi

A polariton is a quasiparticle formed from the coupling of a confined photon in a cavity to electronic excitation, like exciton in a semiconductor. This dissertation reports on series of experiments in confined polariton interaction by design, fabrication, ...

EPFL2021

Bosonic superfluid transport in a quantum point contact

Jean-Philippe Brantut

We present a microscopic theory of heat and particle transport of an interacting, low-temperature Bose- Einstein condensate in a quantum point contact.We show that, in contrast to charged, fermionic superconductors, bosonic systems feature tunneling proces ...

2020

Breakdown of the Wiedemann-Franz law in a unitary Fermi gas

Jean-Philippe Brantut, Samuel Häusler

We report on coupled heat and particle transport measurements through a quantum point contact (QPC) connecting two reservoirs of resonantly interacting, finite temperature Fermi gases. After heating one of them, we observe a particle current flowing from c ...

National Academy of Sciences2018

Light-Matter Interaction in III-Nitride Waveguides: Propagating Polaritons and Optical Gain

Joachim Armand Simonne Ciers

III-nitride waveguides featuring AlInN claddings and GaN/AlGaN quantum wells (QWs) offer promising perspectives for applications in many fields of short-wavelength photonics. Thanks to their nearly lattice-matched nature, these structures exhibit an excell ...

EPFL2018

Mastering the statistical properties of microcavity polaritons

Albert Adiyatullin

Microcavity polaritons are hybrid quasiparticles emerging from the strong coupling between quantum well excitons and light in the resonator. Their unique half-light half-matter nature brings in specific properties like low effective mass, nonlinearity due ...

EPFL2017

Unscreened plasmon dispersion of 2H transition metal dichalcogenides

Helmuth Berger

The plasmon dispersion in 2H transition metal dichalcogenides has been reported to be negative, which is a strong renormalization with respect to the expectations for a homogeneous electron gas. This has been interpreted to be either due to the interaction ...

Amer Physical Soc2017

Noise-Induced Phenomena in Collective Spinor Polariton Excitations

Hadis Abbaspour

Polaritons are quasiparticles resulting from the strong coupling between photons and excitons embedded in a semiconductor microcavity. The exciton component of polaritons provides strong nonlinear interactions, while their photonic counterpart facilitates ...

EPFL2015

Temporally resolved second-order photon correlations of exciton-polariton Bose-Einstein condensate formation

Benoît Marie Joseph Deveaud, Marcia Portella Oberli, Hadis Abbaspour, Albert Adiyatullin, Mitchell David Anderson

Second-order time correlation measurements with a temporal resolution better than 3 ps were performed on a CdTe microcavity where spontaneous Bose-Einstein condensation is observed. After the laser pulse, the nonresonantly excited thermal polariton populat ...

American Institute of Physics2015

Ultrafast Broadband Spectroscopy on Correlated Materials

Andreas Helmut Christian Mann

This thesis deals with femtosecond broadband spectroscopy in the visible regime, which is used to study strongly correlated electron systems. The materials that were studied are high-temperature cuprate superconductors of various dopings and the charge-den ...

EPFL2015

Monitoring Charge Carrier Dynamics at Atomic Length Scales by STM-induced Luminescence

Christoph Grosse

The goal of this thesis is the combination of the high spatial resolution of scanning tunneling microscopy (STM) with the high temporal resolution of optical spectroscopy, by monitoring the light emitted from the tunnel junction. Two complementary techniqu ...

EPFL2015

Refractive index sensing with Fano resonant plasmonic nanostructures: a symmetry based nonlinear approach

Olivier Martin, Jérémy Butet

Sensing using surface plasmon resonances is one of the most promising practical applications of plasmonic nanostructures and Fano resonances allow achieving a lower detection limit thanks to their narrow spectral features. However, a narrow spectral width ...

Royal Society of Chemistry2014

Build up of off-diagonal long-range order in microcavity exciton-polaritons across the parametric threshold

We report an experimental study of the spontaneous spatial and temporal coherence of polariton condensates generated in the optical parametric oscillator configuration, below and at the parametric threshold, and as a function of condensate area. Above the ...

Optical Soc Amer2013

Penrose-Onsager Criterion Validation in a One-Dimensional Polariton Condensate

Benoît Marie Joseph Deveaud, Konstantinos Lagoudakis, Francesco Manni

We perform quantum tomography on one-dimensional polariton condensates, spontaneously occurring in linear disorder valleys in a CdTe planar microcavity sample. By the use of optical interferometric techniques, we determine the first-order coherence functio ...

Amer Physical Soc2012

Semiclassical approach to ground-state properties of hard-core bosons in two dimensions

Frédéric Mila, Tommaso Coletta, Nicolas Laflorencie

Motivated by some inconsistencies in the way quantum fluctuations are included beyond the classical treatment of hard-core bosons on a lattice in the recent literature, we revisit the large-S semiclassical approach to hard-core bosons on the square lattice ...

2012

Physics of Polariton Condensates in GaN-based Planar Microcavities

Jacques Levrat

Since its prediction in 1996 by Imamoğlu and coworkers, the use of a non-equilibrium polariton condensate to produce an intense coherent light source referred to as a polariton laser has attracted a lot of interest in the whole physics community as it ...

EPFL2012

On the condensation of polaritons

Benoît Marie Joseph Deveaud

Bose-Einstein condensates (BECs), the "fifth state of matter," have in fact been discovered by chance both in liquid helium and in superconductors. Since these early encounters, BECs have been sought for, both in atom vapors and in solids. Here we report o ...

2012

Phase-Resolved Imaging of Exciton Polaritons

Gaël Nardin

In this PhD thesis, new imaging techniques have been developed in order to explore the physics of semiconductor microcavities. In these structures, composite bosons called exciton polaritons are the result of strong coupling between the cavity mode and qua ...

EPFL2011

Nonlinear Spectroscopy of a Dissipative Polariton Quantum Fluid

Verena Kohnle

After the observation of Bose-Einstein condensation in the solid state in 2006 and the demonstration on its superfluid character in 2009 the interest for the demonstration of the underlying elementary excitations – the Bogoliubov excitations – was growing. ...

EPFL2011

Condensate-Free Superfluid Induced by the Frustrated Proximity Effect

Frédéric Mila, Nicolas Laflorencie

Since the discovery of superfluidity in He-4 and Landau's phenomenological theory, the relationship between Bose condensation and superfluidity has been intensely debated. He-4 is known by now to be both superfluid and condensed at low temperature, and mor ...

2011