Near-field, back-action cooling and amplification

Abstract

Plasmonic structures produce well-known enhancement of the near-field optical intensity due to sub-wavelength optical confinement. These properties can produce a significant change of transmission and reflection upon small mechanical change of the antenna configuration. We have developed a method based on this enhanced sensitivity for cooling and amplification of a moving mirror. Using finite difference time domain method and standard optomechanical coupled-equation, different regimes of operation such as laser detuning and cavity length were studied to compare the effect of the near-field enhancement with the conventional radiation pressure. Using practical microcavity parameters, we demonstrate significantly higher cooling - or amplification- efficiency for the near-field plasmonic effect. Moreover, the volume of the system is very small. We believe that the significant efficiency improvement and reduced volume due to the proposed near-field effect can make this approach practical for many applications ranging from gravitational wave detection to photonic clocks, high precision accelerometers, atomic force microscopy, laser cooling and parametric amplification.