Selfcomplementary quantum channels

TL;DR

This paper introduces and analyzes selfcomplementary quantum channels, which can model approximate quantum copying, highlighting their properties, non-Markovian dynamics, and potential for preserving quantum coherence and entanglement.

Contribution

It provides a parametrization of selfcomplementary channels and investigates their properties, including non-Markovian behavior and coherence preservation.

Findings

Selfcomplementary channels preserve residual coherences.

They exhibit highly non-Markovian dynamics.

These channels can model approximate quantum copying processes.

Abstract

Selfcomplementary quantum channels are characterized by such an interaction between the principal quantum system and the environment that leads to the same output states of both interacting systems. These maps can describe approximate quantum copy machines, as perfect copying of an unknown quantum state is not possible due to the celebrated no-cloning theorem. We provide here a parametrization of a large class of selfcomplementary channels and analyze their properties. Selfcomplementary channels preserve some residual coherences and residual entanglement. Investigating some measures of non-Markovianity we show that time evolution under selfcomplementary channels is highly non-Markovian.