Master equation for cascade quantum channels: a collisional approach

TL;DR

This paper explores how collisional models can derive master equations for cascade quantum channels, analyzing assumptions and showing how to relax them using an interaction picture approach.

Contribution

It introduces a method to relax fundamental assumptions in collisional models for cascade quantum channels through an interaction picture framework.

Findings

Derived a generalized master equation for cascade channels

Identified assumptions that can be lifted in the collisional approach

Provided a framework for more flexible modeling of quantum cascades

Abstract

It has been recently shown that collisional models can be used to derive a general form for the master equations which describe the reduced time evolution of a composite multipartite quantum system, whose components "propagate" in an environmental medium which induces correlations among them via a cascade mechanism. Here we analyze the fundamental assumptions of this approach showing how some of them can be lifted when passing into a proper interaction picture representation.