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Related papers: Bose-Einstein Condensation of Metastable Helium

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Bose-Einstein condensation (BEC) in a gas has now been achieved. Alkali atoms ($^{87}Rb$, $^{23}Na$ and $^{7}Li$) have been cooled to the point of condensation (temperature of 100 nK) using laser cooling and trapping, followed by magnetic…

Quantum Physics · Physics 2016-09-08 Luca Salasnich

We have achieved Bose-Einstein condensation of $^{40}$Ca, the first for an alkaline earth element. The influence of elastic and inelastic collisions associated with the large ground state s-wave scattering length of $^{40}$Ca was measured.…

Quantum Gases · Physics 2009-09-24 Sebastian Kraft , Felix Vogt , Oliver Appel , Fritz Riehle , Uwe Sterr

We have measured the three-body decay of a Bose-Einstein condensate of rubidium ($^{87}$Rb) atoms prepared in the doubly polarized ground state $F=m_F=2$. Our data are taken for a peak atomic density in the condensate varying between…

Statistical Mechanics · Physics 2015-06-25 J. Soding , D. Guery-Odelin , P. Desbiolles , F. Chevy , H. Inamori , J. Dalibard

The recent report of the observation of Bose-Einstein condensation in atomic Hydrogen, characterized by an "anomalous" density spectrum, is shown to be in agreement with the prediction of the existence of two condensates for temperatures…

Statistical Mechanics · Physics 2007-05-23 E. Del Giudice , G. Preparata

We present a study of the effects of temperature upon the excitation frequencies of a Bose-Einstein condensate formed within a dilute gas with a weak attractive effective interaction between the atoms. We use the self-consistent…

Condensed Matter · Physics 2009-10-31 M. J. Davis , D. A. W. Hutchinson , E. Zaremba

We have observed Bose-Einstein condensation of molecules. When a spin mixture of fermionic Li-6 atoms was evaporatively cooled in an optical dipole trap near a Feshbach resonance, the atomic gas was converted into Li_2 molecules. Below 600…

Soft Condensed Matter · Physics 2007-05-23 M. W. Zwierlein , C. A. Stan , C. H. Schunck , S. M. F. Raupach , S. Gupta , Z. Hadzibabic , W. Ketterle

The critical temperature of Bose-Einstein condensation essentially depends on internal properties of the system as well as on the geometry of a trapping potential. The peculiarities of defining the phase transition temperature of…

Quantum Gases · Physics 2017-05-31 V. I. Yukalov , E. P. Yukalova

We report the realization of a BEC of metastable helium-4 atoms (4He*) in an all optical potential. Up to 10^5 spin polarized 4He* atoms are condensed in an optical dipole trap formed from a single, focused, vertically propagating far…

Quantum Gases · Physics 2010-05-31 G. B. Partridge , J. -C. Jaskula , M. Bonneau , D. Boiron , C. I. Westbrook

Bose-Einstein condensation and the $\lambda$-transition are described in molecular detail for bosons interacting with a pair potential. New phenomena are identified that are absent in the usual ideal gas treatment. Monte Carlo simulations…

Statistical Mechanics · Physics 2022-01-20 Phil Attard

Bose-Einstein condensates of sodium atoms have been confined in an optical dipole trap using a single focused infrared laser beam. This eliminates the restrictions of magnetic traps for further studies of atom lasers and Bose-Einstein…

We study the collision dynamics of two Bose-Einstein condensates with their dynamical wave functions modeled by a set of coupled, time-dependent Gross-Pitaevskii equations. Beginning with an effective one-dimensional system, we identify…

Quantum Gases · Physics 2022-03-22 Aaron Wirthwein , Stephan Haas , Sheng-wey Chiow

We study the stability of a Bose-Einstein condensate of harmonically trapped atoms with negative scattering length, specifically lithium 7. Our method is to solve the time-dependent nonlinear Schrodinger equation numerically. For an…

Condensed Matter · Physics 2009-10-31 Antonios Eleftheriou , Kerson Huang

Due to the observation of Bose-Einstein condensation in dilute atomic $^{87}$Rb and $^{23}$Na vapors last year, there is currently a great interest in the properties of a degenerate Bose gas. One aspect that is not yet understood is the…

Condensed Matter · Physics 2007-05-23 M. Bijlsma , H. T. C. Stoof

Helium atoms or hydrogen molecules are believed to be strongly bound within the interstitial channels (between three carbon nanotubes) within a bundle of many nanotubes. The effects on adsorption of a nonuniform distribution of tubes are…

Materials Science · Physics 2009-11-10 F. Ancilotto , M. M. Calbi , S. M. Gatica , M. W. Cole

We study the collision of two Bose-Einstein condensates with pure dipolar interaction. A stationary pure dipolar condensate is known to be stable when the atom number is below a critical value. However, collapse can occur during the…

Statistical Mechanics · Physics 2009-10-12 B. Sun , M. S. Pindzola

Phase transitions, as the condensation of a gas to a liquid, are often revealed by a discontinuous behavior of thermodynamic quantities. For liquid Helium, for example, a divergence of the specific heat signals the transition from the…

Quantum Gases · Physics 2016-05-02 Tobias Damm , Julian Schmitt , Qi Liang , David Dung , Frank Vewinger , Martin Weitz , Jan Klaers

We report the first detailed decay studies of trapped metastable (2S) hydrogen. By two-photon excitation of ultracold H samples, we have produced clouds of at least 5x10^7 magnetically trapped 2S atoms at densities greater than 4x10^10…

In this work we analyze a non--interacting one dimensional polymer Bose--Einstein condensate in an harmonic trap within the semiclassical approximation. We use an effective Hamiltonian coming from the polymer quantization that arises in…

General Relativity and Quantum Cosmology · Physics 2015-06-12 E. Castellanos , G. Chacon-Acosta

We perform a theoretical analysis of atomic four-wave mixing via a collision of two Bose-Einstein condensates of metastable helium atoms, and compare the results to a recent experiment. We calculate atom-atom pair correlations within the…

We experimentally and theoretically study the peak fraction of a Bose-Einstein condensate loaded into a cubic optical lattice as the lattice potential depth and entropy per particle are varied. This system is well-described by the…

Quantum Gases · Physics 2015-06-23 David McKay , Ushnish Ray , Stefan Natu , Philip Russ , David Ceperley , Brian DeMarco