Optimized production of large Bose Einstein Condensates

Abstract

We suggest different simple schemes to efficiently load and evaporate a ''dimple'' crossed dipolar trap. The collisional processes between atoms which are trapped in a reservoir load in a non adiabatic way the dimple. The reservoir trap can be provided either by a dark SPOT Magneto Optical Trap, the (aberrated) laser beam itself or by a quadrupolar or quadratic magnetic trap. Optimal parameters for the dimple are derived from thermodynamical equations and from loading time, including possible inelastic and Majorana losses. We suggest to load at relatively high temperature a tight optical trap. Simple evaporative cooling equations, taking into account gravity, the possible occurrence of hydrodynamical regime, Feshbach resonance processes and three body recombination events are given. To have an efficient evaporation the elastic collisional rate (in s${}^{-1}$) is found to be on the order of the trapping frequency and lower than one hundred times the temperature in micro-Kelvin. Bose Einstein condensates with more than $10^7$ atoms should be obtained in much less than one second starting from an usual MOT setup.

14 pages

References in corpus (8)

• Three-body recombination at large scattering lengths in an ultracold atomic gas
• Scattering Length Scaling Laws for Ultracold Three-Body Collisions
• Limits on Universality in Ultracold Three-Boson Recombination
• Optimized production of a cesium Bose-Einstein condensate
• Production of a chromium Bose-Einstein condensate
• All-optical generation and photoassociative probing of sodium Bose-Einstein condensates
• Bose-Einstein Condensation in a CO_2-laser Optical Dipole Trap
• Experimental Evidence for Efimov Quantum States

Cited by in corpus (4)

• All-Optical Production of Chromium Bose-Einstein Condensates
• Bose-Einstein condensate in a harmonic trap decorated with Dirac delta functions
• Thermodynamical approaches to efficient sympathetic cooling in ultracold Fermi-Bose atomic mixtures
• Accumulation and thermalization of cold atoms in a finite-depth magnetic trap