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We investigate theoretically the molecular yield in photoassociation of Bose-Einstein condensed sodium atoms for light intensities of the order of and above those applied in a recent experiment. Our results show that the rate at which…

Other Condensed Matter · Physics 2008-09-08 Thomas Gasenzer

Incoherent Thomson scattering is a non-intrusive technique commonly used for measuring local plasma density. Within low-density, low-temperature plasma's and for sufficient laser intensity, the laser may perturb the local electron density…

Plasma Physics · Physics 2018-05-29 Andrew T. Powis , Mikhail N. Shneider

At present, there is considerable interest in using atomic fermions in optical lattices to emulate the mathematical models that have been used to study strongly correlated electronic systems. Some of these models, such as the two…

Quantum Gases · Physics 2015-05-13 Tin-Lun Ho , Qi Zhou

In this letter, atom optic techniques are proposed to control the excitation of a Bose-Einstein condensate in an atomic trap. We show that by employing the dipole potential induced by four highly detuned travelling-wave laser beams with…

Statistical Mechanics · Physics 2009-10-30 Karl-Peter Marzlin , Weiping Zhang

Calculation of the Shannon information entropy (S) and its connection with the order-disorder transition, and with inter-particle interaction provide a challenging research area in the field of quantum information. Experimental progress…

We study the propagation of a non-interacting atom laser distorted by the strong lensing effect of the Bose-Einstein Condensate (BEC) from which it is outcoupled. We observe a transverse structure containing caustics that vary with the…

Other Condensed Matter · Physics 2010-03-19 J. -F. Riou , W. Guerin , Y. Le Coq , M. Fauquembergue , Philippe Bouyer , V. Josse , Alain Aspect

We describe a simple and compact single-chamber apparatus for robust production of $^87$Rb Bose-Einstein condensates. The apparatus is built from off-the-shelf components and allows production of quasi-pure condensates of > $3\times 10^5$…

By making use of a recently proposed framework for the inference of thermodynamic irreversibility in bosonic quantum systems, we experimentally measure and characterize the entropy production rates in the non-equilibrium steady state of two…

A self-consistent mean-field theory for bosons for T>0 is used to reconcile predictions of collapse with recent observations of Bose-Einstein condensation of 7Li. Eigenfunctions of a (non-separable) Hamiltonian that includes the anisotropic…

Condensed Matter · Physics 2009-10-28 T. Bergeman

We explore quantum many-body physics of a driven Bose-Einstein condensate in optical lattices. The laser field induces a gap in the generalized Bogoliubov spectrum proportional to the effective Rabi frequency. The lowest lying modes in a…

Quantum Gases · Physics 2018-04-11 Gavriil Shchedrin , Daniel Jaschke , Lincoln D. Carr

We present neutron scattering measurements of the atomic momentum distribution, n(k), in solid helium under a pressure p = 41 bars and at temperatures between 80 mK and 500 mK. The aim is to determine whether there is Bose-Einstein…

Statistical Mechanics · Physics 2009-11-13 S. O. Diallo , J. V. Pearce , R. T. Azuah , O. Kirichek , J. W. Taylor , H. R. Glyde

We demonstrate the fast accumulation of Cr atoms in a conservative potential from a magnetically guided atomic beam. Without laser cooling on a cycling transition, a single dissipative step realized by optical pumping allows to load atoms…

Quantum Gases · Physics 2015-05-27 Markus Falkenau , Valentin V. Volchkov , Jahn Rührig , Axel Griesmaier , Tilman Pfau

This thesis describes the observation and study of Bose-Einstein condensation of a trapped, dilute gas of atomic hydrogen. The condensate and normal gas are studied by two-photon spectroscopy of the 1S-2S transition. We condense over 10^9…

Atomic Physics · Physics 2007-05-23 Dale G. Fried

Based on the recently introduced averaging procedure in phase space, a new type of entropy is defined on the von Neumann lattice. This quantity can be interpreted as a measure of uncertainty associated with simultaneous measurement of the…

Quantum Physics · Physics 2009-11-07 Sumiyoshi Abe , J. Zak

We present a theoretical model for a coherent terahertz radiation source based on Bose-Einstein condensate of incoherently pumped microcavity photons. Energy relaxation is provided by inelastic photon scattering on a two-dimensional…

Quantum Gases · Physics 2025-09-12 Timofey V. Maximov , Norayr A. Asriyan , Igor L. Kurbakov , Yurii E. Lozovik

Experimental and theoretical results about entropy limits for macroscopic and single-particle systems are reviewed. It is clarified when it is possible to speak about a quantum of entropy, given by the Boltzmann constant k, and about a…

Quantum Physics · Physics 2023-11-06 Uwe Hohm , Christoph Schiller

The distinction between a classical liquid and a classical ordered solid is easy and depends on their different symmetries. The distinction between a classical glass and a classical liquid is more difficult, since the glass is also…

Statistical Mechanics · Physics 2009-11-10 Moshe Schwartz

The density of bosonic states are calculated for spinless free massive bosons in generalised d dimensions. The number of bosons are calculated in the lowest energy state. The Bose Einstein condensation was found in generalised dimensions…

Statistical Mechanics · Physics 2013-04-02 Ajanta Bhowal , Muktish Acharyya

We present an optimized strategy for the production of tightly confined Bose-Einstein condensates (BEC) of 87Rb in a crossed dipole trap with direct loading from a magneto-optical trap. The dipole trap is created with light of a…

Quantum Gases · Physics 2011-11-03 Thomas Lauber , Johannes Kueber , Oliver Wille , Gerhard Birkl

We study the Bose-Einstein condensation of photons in a plasma, where we include the cases of both transverse photons and plasmons. We consider four-wave mixing processes of photon and plasmon modes in a relativistic isotropic plasma to…

Quantum Gases · Physics 2017-06-28 J. T. Mendonça , H. Terças