Related papers: Cavity-Controlled Collective Scattering at the Rec…
We investigate gravitational analogue models to describe slowly rotating objects (e.g., dark-matter halos, or boson stars) in terms of Bose-Einstein condensates, trapped in their own gravitational potentials. We begin with a modified…
We present a theoretical analysis of excitation modes in Bose-Einstein condensates in ultracold alkali-metal gases for large scattering lengths and momenta where corrections to the mean field approximation become important. We assume that…
We examine the Bose-Einstein-condensate (BEC) equivalent of transverse aspects of laser resonators. We model numerically repeated focussing of a 2-dimensional BEC, which could be achieved in practice by a series of far off-resonant light…
We study low-lying collective modes of a horizontally elongated 87Rb condensate produced in a 3D magnetic harmonic trap with the addition of a 1D periodic potential which is provided by a laser standing-wave along the horizontal axis. While…
We excite the lowest-lying quadrupole mode of a Bose-Einstein condensate by modulating the atomic scattering length via a Feshbach resonance. Excitation occurs at various modulation frequencies, and resonances located at the natural…
Light thermalised at room temperature in an optically pumped, dye-filled microcavity resembles a model system of non-interacting Bose-Einstein condensation in the presence of dissipation. We have experimentally investigated some of the…
In this paper we investigate the ground-state properties and related quantum phase transitions for the two-component Bose-Einstein condensate in a single-mode optical cavity. Apart from the usual normal and superradiant phases multi-stable…
Rayleigh scattering is usually considered to be the elastic scattering of photons from sub-wavelength physical objects, such as small particles or molecules. Here, we present the spectroscopic study of the scattering properties of molecules…
We study the scattering properties of a Bose-Einstein condensate held in a finite depth well when the incoming particles are identical to the ones in the condensate. We calculate phase shifts and corresponding transmission and reflection…
We study superradiant scattering off Bose-Einstein condensates by solving the semiclassical Maxwell-Schroedinger equations describing the coupled dynamics of matter-wave and optical fields. Taking the spatial dependence of these fields…
The interplay between disorder and interactions is a "leit-motiv" of condensed matter physics, since it constitutes the driving mechanism of the metal-insulator transition. Bose-Einstein condensates in optical potentials are proving to be…
We report on the observation of quantum coherence of Bose-Einstein condensed photons in an optically-pumped, dye-filled microcavity. We find that coherence is long-range in space and time above condensation threshold, but short-range below…
We study quantum transport of an interacting Bose-Einstein condensate in a two-dimensional disorder potential. In the limit of vanishing atom-atom interaction, a sharp cone in the angle-resolved density of the scattered matter wave is…
We show that a Bose-Einstein condensate emits atoms, if either the condensate wave function, or the scattering length of the atoms depends strongly on time. Moreover, the emission process is coherent and atoms can oscillate back and forth…
Here we report the measurement of thermal photon statistics from a semiconductor photon Bose-Einstein condensate operating just above the condensation threshold. We identify a regime where coherent, single mode emission occurs while still…
We study the effects of random scatterers on the ground state of the one-dimensional Lieb-Liniger model of interacting bosons on the unit interval in the Gross-Pitaevskii regime. We prove that Bose Einstein condensation survives even a…
The influence of a weak random potential on the collective modes of a trapped interacting Bose-Einstein condensate at zero temperature is calculated in the limit when the correlation length of the disorder is smaller than the healing length…
We present a theoretical investigation of optical self-focusing effects in light scattering with condensates. Using long (>200 \mu s), red-detuned pulses we show numerically that a non-negligible self-focusing effect is present that causes…
We study the rotational properties of a two-component Bose-Einstein condensed gas of distinguishable atoms which are confined in a ring potential using both the mean-field approximation, as well as the method of diagonalization of the…
We show that stimulated scattering of an isolated system of N Bose particles with initially broad energy distribution can yield condensation of particles into excited collective state in which most of the bosons occupy one or several modes.…