Related papers: Atomic interaction effects in the superradiant lig…
We have measured the quantum depletion of an interacting homogeneous Bose-Einstein condensate, and confirmed the 70-year old theory of N.N. Bogoliubov. The observed condensate depletion is reversibly tuneable by changing the strength of the…
Rydberg atoms immersed in a Bose-Einstein condensate interact with the quantum gas via electron-atom and ion-atom interaction. To suppress the typically dominant electron-neutral interaction, Rydberg states with principal quantum number up…
The spectrum of light scattered from a Bose-Einstein condensate is studied in the limit of particle-number conservation. To this end, a description in terms of deformed bosons is invoked and this leads to a deviation from the usual predict…
We demonstrate an atom laser using all-optical techniques. A Bose-Einstein condensate of rubidium atoms is created by direct evaporative cooling in a quasistatic dipole trap realized with a single, tightly focused CO$_{2}$-laser beam. An…
We theoretically study the propagation of light through a cold atomic medium, where the effects of motion, laser intensity, atomic density, and polarization can all modify the properties of the scattered light. We present two different…
We demonstrate time-resolved counting of single atoms extracted from a weakly interacting Bose-Einstein condensate of $^{87}$Rb atoms. The atoms are detected with a high-finesse optical cavity and single atom transits are identified. An…
The effect of noise induced by gravitons on a Bose-Einstein condensate has been explored in (Phys. Rev. D 110 (2024) 026014; https://link.aps.org/doi/10.1103/PhysRevD.110.026014). In the previous paper, we investigated the effects of…
We present a model describing the decay of a Bose-Einstein condensate, which assumes the system to remain in thermal equilibrium during the decay. We show that under this assumption transfer of atoms occurs from the condensate to the…
The wave function of an atom passed through a diffraction grating acquires a regular space structure and the interaction of another particle with this atom can be thought of as scattering on a 'quantum grating' composed of a single atom.…
We propose a method for simulating a single realization of a collision of two Bose--Einstein condensates. Recently in Zi\'{n} {\it et al.} (Phys. Rev. Lett. {\bf 94}, 200401 (2005)) we introduced a quantum model of an incoherent elastic…
The density of two {\it initially independent} condensates which are allowed to expand and overlap can show interferences as a function of time due to interparticle interaction. Two situations are separately discussed and compared: (1) all…
We realize textbook experiments on Bose-Einstein condensate tunnelling through thin repulsive potential barriers. In particular, we demonstrate atom tunnelling though a single optical barrier in the quantum scattering regime where the De…
We discuss effects of reflective scattering for heavy nuclei collisions and the deconfined matter formation at the LHC and asymptotical energies. Reflective scattering in hadron collisions leads to decreasing matter density with energy…
The sonic analogue of Hawking radiation can now be experimentally recreated in Bose-Einstein Condensates that contain an acoustic black hole. In these experiments the signal strength and analogue Hawking temperature increase for denser…
A Bose-Einstein condensate of ultracold atoms inside the field of a laser-driven optical cavity exhibits dispersive optical bistability. We describe this system by using mean-field approximation and by analyzing the correlation functions of…
Quantum reflection is a universal property of atoms and molecules when scattered from surfaces in ultracold collisions. Recent experimental work has documented the quantum reflection and diffraction of He atoms, dimers, trimers and Neon…
We study the dynamics of a Bose-Einstein condensate in a one-dimensional optical lattice in the limit of weak atom-atom interactions, including an approximate model for quantum fluctuations. A pulsating dynamical instability in which atoms…
The experimental demonstration of Bose-Einstein condensation in atomic vapors has rapidly lead to new advances in atom optics. It is now well established that two-body collisions play for matter waves a role analogous to that of a Kerr…
We consider a massive complex scalar field with contact interactions with a source and show that, upon Bose-Einstein condensation, there is an emergent long-range interaction between sources. This interaction becomes long-range in the limit…
Using a specially tuned mean-field Bose gas as a reference system, we establish a positive lower bound on the condensate density for continuous Bose systems with superstable two-body interactions and a finite gap in the one-particle…