Journal ArticleDOI
Observation of Bose-Einstein Condensation in a Dilute Atomic Vapor
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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
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Measurements of temperature scaling laws in an optically dense magneto-optical trap
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Critical infrastructures: a review from a complex adaptive systems perspective
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Optical forces on particles of arbitrary shape and size
TL;DR: In this article, a theory of optical forces on particles of arbitrary shape and size and with fields of arbitrary spatial profiles is presented, which applies to particle-light interactions in every optical regime: Rayleigh, Mie and geometrical.
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Fermionizing a small gas of ultracold bosons
TL;DR: In this paper, the authors studied the physics of a rapidly rotating gas of ultracold atomic bosons, with an internal degree of freedom, and showed that in the limit of rapid rotation of the trap the problem exactly maps onto that of noninteracting fermions with spin in the lowest Landau level.
Journal ArticleDOI
Calorimetry of a Bose–Einstein-condensed photon gas
Tobias Damm,Julian Schmitt,Qi Liang,Qi Liang,David Dung,Frank Vewinger,Martin Weitz,Jan Klaers,Jan Klaers +8 more
TL;DR: This work examines the thermodynamic behaviour of a trapped two-dimensional photon gas, a system that allows us to spectroscopically determine the specific heat and the entropy of a nearly ideal Bose gas from the classical high temperature to the Bose-condensed quantum regime.
References
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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.
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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.
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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.
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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.
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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.