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تسجيل مستخدم جديدSingle-photon cooling at the limit of trap dynamics: Maxwells Demon near maximum efficiency
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We demonstrate a general and efficient informational cooling technique for atoms which is an experimental realization of a one-dimensional Maxwells Demon. The technique transfers atoms from a magnetic trap into an optical trap via a single spontaneous Raman transition which is discriminatively driven near each atoms classical turning point. In this way, nearly all of the atomic ensembles kinetic energy in one dimension is removed. We develop a simple analytical model to predict the efficiency of transfer between the traps and provide evidence that the performance is limited only by particle dynamics in the magnetic trap. Transfer efficiencies up to 2.2% are reported. We show that efficiency can be traded for phase-space compression, and we report compression up to a factor of 350. Our results represent a 15-fold improvement over our previous demonstration of the cooling technique.
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