The influence of the Earth’s curved spacetime on Gaussian quantum coherence

@article{Liu2019TheIO,
  title={The influence of the Earth’s curved spacetime on Gaussian quantum coherence},
  author={Tonghua Liu and Shumin Wu and Shuo Cao},
  journal={Laser Physics Letters},
  year={2019}
}
Light wave-packets propagating from the Earth to satellites will be deformed by the curved background spacetime of the Earth, thus influencing the quantum state of light. We show that Gaussian coherence of photon pairs, which are initially prepared in a two-mode squeezed state, is affected by the curved spacetime background of the Earth. We demonstrate that quantum coherence of the state increases for a specific range of height h and then gradually approaches a finite value with further… 

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