Macrorealism inequality for optoelectromechanical systems

@article{Lambert2011MacrorealismIF,
  title={Macrorealism inequality for optoelectromechanical systems},
  author={Neill Lambert and Robert Johansson and Franco Nori},
  journal={Physical Review B},
  year={2011},
  volume={84},
  pages={245421}
}
We show how to apply the Leggett-Garg inequality to opto-electro-mechanical systems near their quantum ground state. We find that by using a dichotomic quantum nondemolition measurement (via, e.g., an additional circuit-QED measurement device), either on the cavity or on the nano-mechanical system itself, the Leggett-Garg inequality is violated. We argue that only measurements on the mechanical system itself give a truly unambigous violation of the Leggett-Garg inequality for the mechanical… 
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