Journal ArticleDOI
Observation of Bose-Einstein Condensation in a Dilute Atomic Vapor
TLDR
A Bose-Einstein condensate was produced in a vapor of rubidium-87 atoms that was confined by magnetic fields and evaporatively cooled and exhibited a nonthermal, anisotropic velocity distribution expected of the minimum-energy quantum state of the magnetic trap in contrast to the isotropic, thermal velocity distribution observed in the broad uncondensed fraction.Abstract:
A Bose-Einstein condensate was produced in a vapor of rubidium-87 atoms that was confined by magnetic fields and evaporatively cooled. The condensate fraction first appeared near a temperature of 170 nanokelvin and a number density of 2.5 x 10 12 per cubic centimeter and could be preserved for more than 15 seconds. Three primary signatures of Bose-Einstein condensation were seen. (i) On top of a broad thermal velocity distribution, a narrow peak appeared that was centered at zero velocity. (ii) The fraction of the atoms that were in this low-velocity peak increased abruptly as the sample temperature was lowered. (iii) The peak exhibited a nonthermal, anisotropic velocity distribution expected of the minimum-energy quantum state of the magnetic trap in contrast to the isotropic, thermal velocity distribution observed in the broad uncondensed fraction.read more
Citations
More filters
Journal ArticleDOI
Bounds on collapse models from cold-atom experiments
Marco Maria Bilardello,Marco Maria Bilardello,Sandro Donadi,Sandro Donadi,Andrea Vinante,Angelo Bassi,Angelo Bassi +6 more
TL;DR: In this paper, the authors considered a recent experiment (Kovachy et al., 2015) where an atomic ensemble was cooled down to picokelvins and showed that the spontaneous localization mechanism of collapse models induces a Brownian motion in all physical systems.
Journal Article
Quantum Hall physics in rotating Bose-Einstein condensates
TL;DR: In this paper, a review of the theoretical and experimental work done to date in exploring quantum Hall physics in cold bosonic gases is presented, in particular the idea of exploiting some of these strongly correlated quantum-Hall-type states in the context of topological quantum computing.
Journal ArticleDOI
Quantum dynamics of rovibrational transitions in H2-H2 collisions: Internal energy and rotational angular momentum conservation effects
S. Fonseca dos Santos,Naduvalath Balakrishnan,Stephen Lepp,Goulven Quéméner,Robert C. Forrey,Robert J. Hinde,Phillip C. Stancil +6 more
TL;DR: A full dimensional quantum mechanical treatment of collisions between two H(2) molecules over a wide range of energies is presented, finding inelastic collisions that conserve the total rotational angular momentum of the diatoms and that involve small changes in the internal energy are found to be highly efficient.
Journal ArticleDOI
Best mean-field for condensates
TL;DR: In this article, a mean-field approach allowing for bosons to reside in several different one-particle functions is presented, where the number of bosons in each of these functions is a variational parameter minimizing the energy.
Journal ArticleDOI
Dynamics of rotating two-component Bose-Einstein condensates and its efficient computation
TL;DR: In this article, the authors investigated the dynamics of rotating two-component Bose-Einstein condensates based on the coupled Gross-Pitaevskii equations with an angular momentum rotation term and an external driving field, and proposed an efficient and accurate method for numerical simulations.
References
More filters
Proceedings Article
Bose-Einstein condensation in a gas of sodium atoms
TL;DR: The striking signature of Bose condensation was the sudden appearance of a bimodal velocity distribution below the critical temperature of ~2µK.
Journal ArticleDOI
Trapping of neutral sodium atoms with radiation pressure
TL;DR: The confinement and cooling of an optically dense cloud of neutral sodium atoms by radiation pressure was reported, provided by three retroreflected laser beams propagating along orthogonal axes, with a weak magnetic field used to distinguish between the beams.
Journal ArticleDOI
Plancks Gesetz und Lichtquantenhypothese
TL;DR: In this article, the authors describe how the Phasenraum eines Lichtquants in bezug auf ein gegebenes Volumen wird in „Zellen“ von der Grose h3 aufgeteilt, i.e., the Zahl der moglichen Verteilungen der Lichtquanten einer makroskopisch definierten Strahlung unter diese Zellen liefert die Entropie.
Journal ArticleDOI
Observation of atoms laser cooled below the Doppler limit
Paul D. Lett,Richard N. Watts,Christoph I Westbrook,William D. Phillips,Phillip L. Gould,Harold Metcalf +5 more
TL;DR: This "Doppler cooling limit" results from the minimization of the detuning-dependent temperature at low laser power1.
Journal ArticleDOI
Output Coupler for Bose-Einstein Condensed Atoms
TL;DR: In this paper, an output coupler for Bose condensed atoms in a magnetic trap was demonstrated, where short pulses of rf radiation were used to create Bose condensates in a superposition of trapped and untrapped hyperfine states.