Pseudomode description of general open quantum systems with applications to thermodynamics*

The pseudomode method has been recognized as a powerful tool for the description of non-Markovian open system dynamics. The technique is based on replacing a bosonic environment with a small set of damped harmonic oscillators - the pseudomodes - thereby mapping the initial system onto a simpler configuration described by a Markovian master equation. In this talk, we present an efficient mapping scheme that combines several key features of previous approaches, enabling the optimal construction of pseudomode networks representing general non-Markovian environments. For special cases involving non-Hermitian system-pseudomode interactions, we also establish general conditions under which the corresponding master equation may be converted into Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) form. Finally, we demonstrate the application of our results by analyzing the performance of a quantum Otto cycle at strong system-bath coupling.