Probing the diamagnetic term in light-matter interaction

  title={Probing the diamagnetic term in light-matter interaction},
  author={Matteo A. C. Rossi and Matteo Bina and Matteo G. A. Paris and Marco G. Genoni and Gerardo Adesso and Tommaso Tufarelli},
  journal={arXiv: Quantum Physics},
We address the quantum estimation of the diamagnetic, or $A^2$, term in an effective model of light-matter interaction featuring two coupled oscillators. First, we calculate the quantum Fisher information of the diamagnetic parameter in the interacting ground state. Then, we find that typical measurements on the transverse radiation field, such as homodyne detection or photon counting, permit to estimate the diamagnetic coupling constant with near-optimal efficiency in a wide range of model… 

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