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Achievable rates for the Gaussian quantum channel

Jim Harrington·John Preskill
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Abstract

We study the properties of quantum stabilizer codes that embed a finite-dimensional protected code space in an infinite-dimensional Hilbert space. The stabilizer group of such a code is associated with a symplectically integral lattice in the phase space of 2N canonical variables. From the existence of symplectically integral lattices with suitable properties, we infer a lower bound on the quantum capacity of the Gaussian quantum channel that matches the one-shot coherent information optimized over Gaussian input states.

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Jim Harrington, John Preskill. 2001-05-13. Achievable rates for the Gaussian quantum channel. https://doi.org/10.1103/physreva.64.062301

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