Detecting quantum-coherent nanomechanical oscillations using the   current-noise spectrum of a double quantum dot
  We consider a nanomechanical resonator coupled to a double quantum dot. We demonstrate how the finite-frequency current noise spectrum through the double quantum dot can be used to distinguish classical and quantum behaviour in the nearby nano-electromechanical resonator. We also show how the full frequency current noise spectrum gives important information on the combined double quantum dot-resonator energy spectrum. Finally, we point out regimes where the quantum state of the resonator becomes squeezed, and also examine the cross-correlated electron-phonon current noise. 
Neill Lambert, Franco Nori