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Anomalous optical bistability and robust entanglement of mechanical oscillators using two-photon coherence

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 نشر من قبل Eyob A. Sete
 تاريخ النشر 2014
  مجال البحث فيزياء
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Quantum coherence is one of the most intriguing applications of quantum mechanics, and has led to interesting phenomena and uncommon results. Here we show that in a stark contrast to the usual red-detuned condition to observe bistability in single-mode optomechanics, the optical intensities exhibit bistability for all values of cavity-laser detuning due to intermode coupling induced by the two-photon coherence. Interestingly, an unconventional bistability with ribbon-shaped hysteresis can be observed for blue-detuned laser frequencies. We also demonstrate that the two-photon coherence leads to a strong entanglement between the movable mirrors in the adiabatic regime. Surprisingly, the mirror-mirror entanglement is shown to persist for environment temperature of the phonon bath up to 12 K using experimental parameters.



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