Seminário do Departamento de Física dos Materiais e Mecânica - FMT
“Thermodynamics of energy transfer and energy storage in quantum systems”
Prof. Dr. Carlos Iván Henao Osorio , Centro de Ciências Naturais e Humanas da Universidade Federal do ABC
Dia:19 de junho, terça-feira, às 16h.
Local: Sala de Seminários José Roberto Leite, Edifício Alessandro Volta (bloco C)
Abstract:
The study of thermodynamics in quantum systems is a research field that attracts much attention nowadays. In particular, there has been a great deal of effort to understand how quantum properties affect thermodynamic processes, beyond what is possible by using only classical resources. This search may have important practical consequences, in the optimal design of micro and nano-devices for technological applications. In this seminar I will present some results of my research as a PhD student at UFABC, under the advising of Prof. Roberto Serra. The presentation will be divided into two parts. First, I will talk about energy transfer between two quantum systems of arbitrary (discrete) dimension. The heat flow is a special form of energy transfer, which may follow the opposite direction (i.e., form cold to hot) in systems with initial quantum correlations. We show in Ref. [Phys. Rev. E 97, 062105] that the energy transfer between two qubits is boosted by the presence of quantum coherence in the initial state. In particular, we use this result to rigorously explain the observations of a recent experiment, involving the reversion of the heat flow between a pair of nuclear spins [arXiv:1711.03323]. More generally, we obtain an inequality that embodies the potential of quantum coherence for energy transfer in arbitrary quantum systems. The second part of the talk will be about a model for charging a three-level battery, employing a heat engine of two qubits. Results for the maximum charge of the battery will be presented, under different charging conditions. I will also show that, for some initial states battery, the studied engine can outperform the energy stored through a classical external field.
