Transmission of classical and quantum information through a quantum memory channel with damping

TL;DR

This paper studies how a quantum memory channel with damping affects the transmission of classical and quantum information, showing that memory effects can enhance the channel's capacity.

Contribution

It models a damped harmonic oscillator as a quantum memory channel and proves its forgetfulness, enabling quantum coding theorems for its capacities.

Findings

Memory effects improve information transmission capacity.

Memory channel is forgetful, allowing coding theorems.

Memory influences the channel's transmission properties.

Abstract

We consider the transfer of classical and quantum information through a memory amplitude damping channel. Such a quantum channel is modeled as a damped harmonic oscillator, the interaction between the information carriers - a train of qubits - and the oscillator being of the Jaynes-Cummings kind. We prove that this memory channel is forgetful, so that quantum coding theorems hold for its capacities. We analyze entropic quantities relative to two uses of this channel. We show that memory effects improve the channel aptitude to transmit both classical and quantum information, and we investigate the mechanism by which memory acts in changing the channel transmission properties.