English
Related papers

Related papers: A Large Atom Number Metastable Helium Bose-Einstei…

200 papers

Assuming the existence of a Bose-Einstein condensate composed of the majority of a sample of ultracold, trapped atoms, perturbative treatments to incorporate the non-condensate fraction are common. Here we describe how this may be carried…

Quantum Gases · Physics 2017-08-23 S. A. Gardiner , T. P. Billam

We report a simple method for the creation of Bose-Einstein condensates of $^{85}$Rb by direct evaporation in a crossed optical dipole trap. The independent control of the trap frequencies and magnetic bias field afforded by the trapping…

Atomic Physics · Physics 2013-04-11 A. L. Marchant , S. Händel , S. A. Hopkins , T. P. Wiles , S. L. Cornish

We have studied ionizing collisions in a BEC of He*. Measurements of the ion production rate combined with measurements of the density and number of atoms for the same sample allow us to estimate both the 2 and 3-body contributions to this…

Statistical Mechanics · Physics 2009-11-07 O. Sirjean , S. Seidelin , J. Viana Gomes , D. Boiron , C. I. Westbrook , A. Aspect , G. V. Shlyapnikov

Attempts to create quantum degenerate gases without evaporative cooling have been pursued since the early days of laser cooling, with the consensus that polarization gradient cooling (PGC, also known as "optical molasses") alone cannot…

We report on the all-optical production of Bose-Einstein condensates in microgravity using a combination of grey molasses cooling, light-shift engineering and optical trapping in a painted potential. Forced evaporative cooling in a 3-m high…

We report Bose-Einstein condensation of two isotopes of the highly magnetic element dysprosium: 162Dy and 160Dy. For 162Dy, condensates with 10^5 atoms form below T = 50 nK. We find the evaporation efficiency for the isotope 160Dy to be…

Quantum Gases · Physics 2015-05-13 Yijun Tang , Nathaniel Q. Burdick , Kristian Baumann , Benjamin L. Lev

Using magnetically trapped atomic hydrogen as an example, we investigate the prospects of achieving Bose-Einstein condensation in a dilute Bose gas. We show that, if the gas is quenched sufficiently far into the critical region of the phase…

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

Bose-Einstein condensates have been produced in an optical box trap. This novel optical trap type has strong confinement in two directions comparable to that which is possible in an optical lattice, yet produces individual condensates…

Other Condensed Matter · Physics 2009-11-11 T. P. Meyrath , F. Schreck , J. L. Hanssen , C. -S. Chuu , M. G. Raizen

The experimental realization of a thin layer of spin-polarized hydrogen adsorbed on top of the surface of superfluid 4He provides one of the best examples of a stable nearly two-dimensional quantum Bose gas. We report a theoretical study of…

Quantum Gases · Physics 2015-06-18 J. M. Marin , L. Vranjes Markic , J. Boronat

Path Integral Monte Carlo was used to calculate the Bose-Einstein condensate fraction at the surface of a helium film at $T=0.77 K$, as a function of density. Moving from the center of the slab to the surface, the condensate fraction was…

Condensed Matter · Physics 2009-11-07 E. W. Draeger , D. M. Ceperley

We report an experiment measuring simultaneously the temperatureand the flux of ions produced by a cloud of triplet metastablehelium atoms at the Bose-Einstein critical temperature. The onsetof condensation is revealed by a sharp increase…

It has been recently proposed that helium white dwarfs may provide promising conditions for the occurrence of the Bose-Einstein condensation. The argument supporting this expectation is that in some conditions attained in the core of these…

Solar and Stellar Astrophysics · Physics 2015-05-27 O. G. Benvenuto , M. A. De Vito

Three hyperfine states of Bose-condensed sodium atoms, recently optically trapped, can be described as a spin-1 Bose gas. We study the behaviour of this system in a magnetic field, and construct the phase diagram, where the temperature of…

Statistical Mechanics · Physics 2009-10-31 M. V. Simkin , E. G. D. Cohen

This article describes experiments performed with an ultracold gas of metastable helium above the Bose-Einstein transition. The gas is trapped in an harmonic magnetic potential and collective excitations are induced. Both the frequency and…

Condensed Matter · Physics 2007-05-23 M. Leduc , J. Leonard , F. Pereira dos Santos , E. Jahier , S. Schwartz , C. Cohen-Tannoudji

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 investigate Bose-Einstein condensation of trapped spin-1 atoms with ferromagnetic or antiferromagnetic two-body contact interactions. We adopt the mean field theory and develop a Hartree-Fock-Popov type approximation in terms of a…

Statistical Mechanics · Physics 2007-05-23 Wenxian Zhang , Su Yi , L. You

The dynamics of evaporative cooling of magnetically trapped $^{87}$Rb atoms is studied on the basis of the quantum kinetic theory of a Bose gas. We carried out the quantitative calculations of the time evolution of conventional evaporative…

Statistical Mechanics · Physics 2009-11-10 Makoto Yamashita , Tetsuya Mukai

We report on the realization of a sodium Bose--Einstein condensate (BEC) in a combined red-detuned optical dipole trap, formed by two beams crossing in a horizontal plane and a third, tightly focused dimple trap propagating vertically. We…

Atomic Physics · Physics 2015-05-27 David Jacob , Emmanuel Mimoun , Luigi De Sarlo , Martin Weitz , J. Dalibard , F. Gerbier

Bose-Einstein condensates of $^7$Li have been limited in number due to attractive interatomic interactions. Beyond this number, the condensate undergoes collective collapse. We study theoretically the effect of driving low-lying collective…

Condensed Matter · Physics 2009-10-31 Arjendu K. Pattanayak , Arnaldo Gammal , Charles A. Sackett , Randall G. Hulet

Bose-Einstein condensation, observed in either strongly interacting liquid helium or weakly interacting atomic Bose gases, is widely known to be a second-order phase transition. Here, we predict a first-order Bose-Einstein condensation in a…

Quantum Gases · Physics 2022-01-21 Hui Hu , Zeng-Qiang Yu , Jia Wang , Xia-Ji Liu
‹ Prev 1 3 4 5 6 7 10 Next ›