Exploring the Limits of Open Quantum Dynamics I: Motivation, New Results from Toy Models to Applications

Abstract

Which quantum states can be reached by controlling open Markovian $n$-level quantum systems? Here, we address reachable sets of coherently controllable quantum systems with switchable coupling to a thermal bath of temperature $T$. The core problem reduces to a toy model of studying points in the standard simplex allowing for two types of controls: (i) permutations within the simplex, (ii) contractions by a dissipative semigroup. By illustration, we put the problem into context and show how toy-model solutions pertain to the reachable set of the original controlled Markovian quantum system. Beyond the case $T=0$ (amplitude damping) we present new results for $0<T<\infty$ using methods of $d$-majorisation.

Extended abstract for MTNS 2020; full paper is arXiv:2303.01891. arXiv admin note: text overlap with arXiv:1905.01224

Cited by in corpus (1)

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