Energetic footprints of coherence and irreversibility in the quantum regime

In this quantum thermodynamics [1] talk, I will discuss work extraction in the quantum regime. We set up an optimal quantum thermodynamic process that removes quantum information in analogy to Landauerâ s erasure of classical information. The thermodynamic analysis of this optimal process uncovers that work can be extracted from quantum coherences in addition to the work that can be extracted from classical non-equilibrium states [2]. In the second part of the talk I will discuss how the unavoidable presence of irreversibility affects entropic and energetic exchanges during a non-optimal protocol. I will show that the heat footprint of quantum irreversibility differs markedly from the classical case [3]. The analysis is made possible by employing quantum trajectories that allow to construct distributions for classical heat and quantum heat exchanges. We also quantify how the occurrence of quantum irreversibility reduces the amount of work that can be extracted from a state with coherences. Our results show that decoherence leads to both entropic and energetic footprints which play an important role in the optimization of controlled quantum operations at low temperature, including quantum processors. $$ $$ [1] Quantum thermodynamics, S. Vinjanampathy, J. Anders, Contemporary Physics 57, 545 (2016). $$ $$ [2] Coherence and measurement in quantum thermodynamics, P. Kammerlander, J. Anders, Scientific Reports 6, 22174 (2016). $$ $$ [3] Energetic footprints of irreversibility in the quantum regime, H. Mohammady, A. Auffeves, J. Anders, arXiv:1907.06559Non UBCUnreviewedAuthor affiliation: University of ExeterResearche