Related papers: Bose-Einstein condensation of 2D dipolar excitons:…
Experimentally the temperature in a Bose--Einstein condensate is always deduced resorting to the comparison between the Maxwell--Boltzmann velocity distribution function and the density profile in momentum space. Though a successful method…
Exciton-polaritons - hybrid light-matter quasiparticles - can undergo Bose-Einstein-like condensation at elevated temperatures owing to their lower effective mass. This becomes even more pronounced in the context of molecular polariton…
We study theoretically the collective dynamics of rotational excitations of polar molecules loaded into an optical lattice in two dimensions. These excitations behave as hard-core bosons with a relativistic energy dispersion arising from…
We predict the effect of the roton instability for a two-dimensional weakly interacting gas of tilted dipoles in a single homogeneous quantum layer. Being typical for strongly correlated systems, the roton phenomena appear to occur in a…
Transition temperatures $T_{c}$ calculated using the BCS model electron-phonon interaction without any adjustable parameters agree with empirical values for quasi-2D cuprate superconductors. They follow from a two-dimensional gas of…
We present experiments on the luminescence of excitons confined in a potential trap at milli-Kelvin bath temperatures under cw-excitation. They reveal several distinct features like a kink in the dependence of the total integrated…
We treat the problem of self-consistently interacting bosons in the presence of a finite (but macroscopic) potential well within a quasi-classical approximation for the normal component and the order parameter. We solve the equilibrium…
The object of study of this thesis are dipolar systems in the quantum degenerate regime. In general, dealing with many-body systems and evaluating their properties requires to deal with the Schr\"odinger equation. In the present study we…
Two-species hard-core bosons trapped in a three-dimensional isotropic harmonic potential are studied with the path-integral quantum Monte Carlo simulation. The double condensates show two distinct structures depending on how the external…
Oscillations of atomic Bose-Einstein condensates in a 1D optical lattice with a two-point basis is investigated. In the low-frequency regime, four branches of modes are resolved, that correspond to the transverse in-phase and out-of-phase…
Semiconductor microcavity systems strongly coupled to quantum wells are now receiving a great deal of attention because of their ability to efficiently generate coherent light by the Bose-Einstein condensation (BEC) of an exciton-polariton…
We calculate the pair correlation function of an interacting Bose gas in a harmonic trap directly via Path Integral Quantum Monte Carlo simulation for various temperatures and compare the numerical result with simple approximative…
We demonstrate the spontaneous formation of a Bose-Einstein condensate (BEC) of strongly-bound harmonically-trapped dipolar $^{164}$Dy atoms on the outer curved surface of an elliptical or a circular cylinder, with a distinct topology,…
We investigate the zero-temperature properties of a diluted homogeneous Bose gas made of $N$ particles interacting via a two-body square-well potential by perfor ming Monte Carlo simulations. We tune the interaction strength to achieve…
The Bose-Einstein condensation of correlated atoms in a trap is studied by examining the effect of inter-particle correlations to one-body properties of atomic systems at zero temperature using a simplified formula for the correlated two…
Using classical field approximation we present the first study of statistical properties of one dimensional Bose gas with attractive interaction. The canonical probability distribution is generated with the help of a Monte Carlo method.…
We report on the experimental observation of stimulated cooling in the non-equilibrium Bose-Einstein condensate (BEC) of weakly interacting exciton-polaritons from approximately room temperature down to 20K. By resolving the condensate in…
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…
We investigate the notion of Bose-Einstein condensation of interacting particles. The definition of the condensate is based on the existence of the dominant eigenvalue of the single-particle density matrix. The statistical properties and…
Rotating dipolar Bose-Einstein condensates exhibit rich physics due to the interplay of long-range interactions and rotation, leading to unconventional vortex structures and strongly correlated phases. While most studies rely on mean-field…