Lorentz-invariant mass and entanglement of biphoton states

  title={Lorentz-invariant mass and entanglement of biphoton states},
  author={Stephen Vintskevich and Dmitry A. Grigoriev and Maxim V. Fedorov},
  journal={Laser Physics Letters},
The concept of the Lorentz-invariant mass of a group of particles is shown to be applicable to biphoton states formed in the process of spontaneous parametric down conversion. The conditions are found when the Lorentz-invariant mass is related directly with (proportional to) the Schmidt parameter determining a high degree of entanglement of a biphoton state with respect to transverse wave vectors of emitted photons. 

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  • Lett., 117:64001
  • 2017