Capacity of a bosonic memory channel with Gauss-Markov noise

  title={Capacity of a bosonic memory channel with Gauss-Markov noise},
  author={Joachim Schafer and D. Daems and Evgueni Karpov and Nicolas J. Cerf},
  journal={Physical Review A},
We address the classical capacity of a quantum bosonic memory channel with additive noise, subject to an input energy constraint. The memory is modeled by correlated noise emerging from a Gauss-Markov process. Under reasonable assumptions, we show that the optimal modulation results from a “quantum water-filling” solution above a certain input energy threshold, similar to the optimal modulation for parallel classical Gaussian channels. We also derive analytically the optimal multimode input… 

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