Gustavo Telles

Light-induced atomic desorption for loading a sodium magneto-optical trap

We report studies of photon-stimulated desorption, also known as light-induced atomic desorption, of sodium atoms from a vacuum-cell glass surface used for loading a magneto-optical trap (MOT). Fluorescence detection was used to record the trapped atom number and the desorption rate. We observed a steep wavelength dependence of the desorption process above 2.6 eV photon energy, a result significant for estimations of sodium vapor density in the lunar atmosphere. Our data fit well to a simple model for the loading of the MOT dependent only on the sodium desorption rate and residual gas density. Up to 3.7x10{sup 7} Na atoms were confined under ultrahigh-vacuum conditions, creating promising loading conditions for a vapor-cell-based atomic Bose-Einstein condensate of sodium.

Measuring the heat capacity in a Bose-Einstein condensation using global variables

Phase transitions are well understood and generally followed by the behavior of the associated thermodynamic quantities, such as in the case of the

Collisional losses in a K-Rb cold mixture

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Evidence of a two-color trap-loss channel

point superfluid transition of liquid helium, which is observed in its heat capacity. In the case of a trapped Bose-Einstein condensate (BEC), the heat capacity cannot be directly measured. In this work, we present a technique able to determine the global heat capacity from the density distribution of a weakly interacting gas trapped in an inhomogeneous potential. This approach represents an alternative to models based on local density approximation. By defining a pair of global conjugate variables, we determine the total internal energy and its temperature derivative, the heat capacity. We then apply the technique to a trapped

Twisted unwinding of multi-charged quantum vortex and generation of turbulence in atomic Bose-Einstein condensates

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Decay dynamics of quadruply quantized vortices in a BEC

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First and second global sound velocity of a Bose gas across the transition to Bose-Einstein condensation

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Investigation of the coupling of the momentum distribution of a BEC with its collective of modes

-type transition dependent on the atom number is observed, and the deviations from the non-interacting, ideal gas case are discussed. Finally we discuss the chances of using this method to study the heat capacity at

Characterization of LIAD loaded sodium MOT

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Collision dynamics of magnetically trapped Na and Rb

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