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

• URL: http://arxiv.org/abs/2003.06018v4
• Date: Tue, 28 Mar 2023 20:26:23 GMT
• Title: Exploring the Limits of Open Quantum Dynamics I: Motivation, New Results from Toy Models to Applications
• Authors: Thomas Schulte-Herbr\"uggen, Frederik vom Ende, Gunther Dirr
• Abstract summary: We address reachable sets of coherently controllable quantum systems with switchable coupling to a thermal bath of temperature $T$. 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.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• 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.

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