相关论文: Study on Cooling of Positronium for Bose-Einstein …
Realizing Bose-Einstein condensation of polar molecules is a long-standing challenge in ultracold physics and quantum science due to near-universal two-body collisional losses. Here, we report the production of a Bose-Einstein condensate of…
A theory of Bose-Einstein condensation (BEC) of light in a dye microcavity is developed. The photon polarization degeneracy and the interaction between dye molecules and photons in all of the cavity modes are taken into account. The theory…
The paper considers Bose-Einstein condensation (BEC) of light in a cavity with medium. In the framework of two-level model we show the effect of gaseous medium on the critical temperature of light condensation in the system. Transition of…
We have produced a Bose-Einstein condensate (BEC) on an atom chip using only superconducting wires in a cryogenic environment. We observe the onset of condensation for 10^4 atoms at a temperature of 100 nK. This result opens the way for…
In the first part of this thesis I study the intermediate regime between ordinary lasing and a BEC of exciton polaritons. I take into account the fermionic structure of polaritons, treating the excitons as two-level systems coupled to a…
Recent experimental advances in Positronium (Ps) physics have made it possible to produce dense Ps ensembles in which Ps-Ps interactions may occur, leading to the production of Ps$_2$ molecules and paving the way to the realization of a Ps…
The achievement of Bose-Einstein condensation (BEC) in ultracold vapors of alkali atoms has given enormous impulse to the theoretical and experimental study of dilute atomic gases in condensed quantum states inside magnetic traps and…
We report the simultaneous production of Bose-Einstein condensates (BECs) of $^{87}$Rb and $^{133}$Cs atoms in separate optical traps. The two samples are mixed during laser cooling and loading but are separated by $400 \mu$m for the final…
Polariton thermalization is a key process in achieving light-matter Bose--Einstein condensation, spanning from solid-state semiconductor microcavities at cryogenic temperatures to surface plasmon nanocavities with molecules at room…
We demonstrate a simple scheme to reach Bose-Einstein condensation (BEC) of metastable triplet helium atoms using a single beam optical dipole trap with moderate power of less than 3 W. Our scheme is based on RF-induced evaporative cooling…
We study the Bose-Einstein condensation (BEC) for a system of $^7Li$ atoms, which have negative scattering length (attractive interaction), confined in a harmonic potential. Within the Bogoliubov and Popov approximations, we numerically…
We report on laser cooling of a large fraction of positronium (Ps) in free-flight by strongly saturating the $1^3S$-$2^3P$ transition with a broadband, long-pulsed 243 nm alexandrite laser. The ground state Ps cloud is produced in a…
We investigate the thermal robustness of traveling polariton condensates. We create remote condensates that have never been in contact, and study their interference in momentum space, when they travel with the same velocity, by means of…
A theoretical model is developed for treating super conductive Bose-Einstein condensation (BEC) effects for excitons in planar systems, under the condition that many excitons are included in a surface area, with the dimensions of the…
We present a novel experimental approach to Bose-Einstein condensation by increasing the particle number of the system at almost constant temperature. In particular the emergence of a new condensate is observed in multi-component F=1 spinor…
We report the realization of Bose-Einstein condensates of 39K atoms without the aid of an additional atomic coolant. Our route to Bose-Einstein condensation comprises Sub Doppler laser cooling of large atomic clouds with more than 10^10…
We present a theory for the description of energy relaxation in a nonequilibrium condensate of bosonic particles. The approach is based on coupling to a thermal bath of other particles (e.g., phonons in a crystal, or noncondensed atoms in a…
We study a finite-time thermodynamic refrigeration cycle realized numerically in three-dimensional, weakly interacting Bose-Einstein condensates (BECs). The setup consists of three spatially separated condensates -- system, piston, and…
We report on the generation of a Bose-Einstein condensate in a gas of chromium atoms, which will make studies of the effects of anisotropic long-range interactions in degenerate quantum gases possible. The preparation of the chromium…
In this work we derive a theory of polariton condensation based on the theory of interacting Bose particles. In particular, we describe self-consistently the linear exciton-photon coupling and the exciton-nonlinearities, by generalizing the…