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Synthetic $mathcal{PT}$ Symmetry and Nonreciprocal Amplification in Optomechanics

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 نشر من قبل Jian-Qi Zhang
 تاريخ النشر 2021
  مجال البحث فيزياء
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We propose how to achieve synthetic $mathcal{PT}$ symmetry in optomechanics without using any active medium. We find that harnessing the Stokes process in such a system can lead to the emergence of exceptional point (EP), i.e., the coalescing of both the eigenvalues and the eigenvectors of the system. By encircling the EP,non-reciprocal optical amplification and chiral mode switching can be achieved. This provides a surprisingly simplified route to realize $mathcal{PT}$-symmetric optomechanics, indicating that a wide range of EP devices can be created and utilized for various applications such as topological optical engineering and nanomechanical processing or sensing.

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