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Standard Quantum Limit for Probing Mechanical Energy Quantization

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 نشر من قبل Haixing Miao
 تاريخ النشر 2009
  مجال البحث فيزياء
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We derive a standard quantum limit for probing mechanical energy quantization in a class of systems with mechanical modes parametrically coupled to external degrees of freedom. To resolve a single mechanical quantum, it requires a strong-coupling regime -- the decay rate of external degrees of freedom is smaller than the parametric coupling rate. In the case for cavity-assisted optomechanical systems, e.g. the one proposed by Thompson et al., zero-point motion of the mechanical oscillator needs to be comparable to linear dynamical range of the optical system which is characterized by the optical wavelength divided by the cavity finesse.



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