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تسجيل مستخدم جديدOptimization of ground-state cooling of a mechanical mode using a three-level system
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We propose an optimization scheme for ground-state cooling of a mechanical mode by coupling to a general three-level system. We formulate the optimization scheme, using the master equation approach, over a broad range of system parameters including detunings, decay rates, coupling strengths, and pumping rate. We implement the optimization scheme on three physical systems: a colloidal quantum dot coupled to its confined phonon mode, a polariton coupled to a mechanical resonator mode, and a coupled-cavity system coupled to a mechanical resonator mode. These three physical systems span a broad range of mechanical mode frequencies, coupling rates, and decay rates. Our optimization scheme lowers the stead-state phonon number in all three cases by orders of magnitude. We also calculate the net cooling rate by estimating the phonon decay rate and show that the optimized system parameters also result in efficient cooling. The proposed optimization scheme can be readily extended to any generic driven three-level system coupled to a mechanical mode.
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