Minimum output entropy of a non-Gaussian quantum channel

TL;DR

This paper introduces a non-Gaussian quantum channel model combining amplitude damping and dephasing, identifying states that minimize output entropy under energy constraints, with conjectures supported by numerical evidence.

Contribution

It presents a new non-Gaussian quantum channel model and characterizes states that minimize output entropy, including conjectures for finite-dimensional truncations.

Findings

States approaching zero output entropy under energy constraints

Optimal states exploit infinite-dimensional Hilbert space

Numerical evidence supports conjectured optimal states for truncated spaces

Abstract

We introduce a model of non-Gaussian quantum channel that stems from the combination of two physically relevant processes occurring in open quantum systems, namely amplitude damping and dephasing. For it we find input states approaching zero output entropy, while respecting the input energy constraint. These states fully exploit the infinite dimensionality of the Hilbert space. Upon truncation of the latter, the minimum output entropy remains finite and optimal input states for such a case are conjectured thanks to numerical evidences.