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تسجيل مستخدم جديدPreparation of ultracold atom clouds at the shot noise level
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We prepare number stabilized ultracold clouds through the real-time analysis of non-destructive images and the application of feedback. In our experiments, the atom number ${Nsim10^6}$ is determined by high precision Faraday imaging with uncertainty $Delta_N$ below the shot noise level, i.e., $Delta_N <sqrt{N}$. Based on this measurement, feedback is applied to reduce the atom number to a user-defined target, whereupon a second imaging series probes the number stabilized cloud. By this method, we show that the atom number in ultracold clouds can be prepared below the shot noise level.
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