Multilevel quantum thermodynamic swap engines

Quantum thermodynamic cycles and quantum heat engines.

In order to describe quantum heat engines, here we systematically study isothermal and isochoric processes for quantum thermodynamic cycles. Based on these results the quantum versions of both the Carnot heat engine and the Otto heat engine are defined without ambiguities. We also study the properties of quantum Carnot and Otto heat engines in comparison with their classical counterparts. Relat...

Designing optimal discrete-feedback thermodynamic engines

Feedback can be utilized to convert information into useful work, making it an effective tool for increasing the performance of thermodynamic engines. Using feedback reversibility as a guiding principle, we devise a method for designing optimal feedback protocols for thermodynamic engines that extracts all the information gained during feedback as work. Our method is based on the observation th...

Supplementary Information for Quantum heat engines: A thermodynamic analysis of power and efficiency

Limits of Quantum Engines

Could scientists use the Second Law of Thermodynamics on your chewing muscles to work out when you are going to die? According to research published in the International Journal of Exergy, the level of entropy, or thermodynamic disorder, in the chewing muscles in your jaw increases with each mouthful. This entropy begins to accumulate from the moment you're "on solids" until your last meal, but...

Entanglement and swap of quantum states

Suppose that two distant parties Alice and Bob share an entangled state ρAB, and they want to exchange the subsystems of ρAB by local operations and classical communication (LOCC). In general, this LOCC task (i.e. the LOCC transformation of ρAB → V ρABV with V being a swap operator) is impossible deterministically, but becomes possible probabilistically. We study how the optimal probability is ...