M. Horodecki (Intl. Cen. for Theory of Quantum Technologies): Minimal-coupling quantum heat engines
Channel: Centrum Fizyki Teoretycznej PAN
Date: 15/04/2021

M. Horodecki (International Centre for Theory of Quantum Technologies, Gdańsk)
Minimal-coupling quantum heat engines
We consider a paradigm for discrete quantum heat machines where we allow only for coupling two systems at a time, and there is explicit battery. The evolution in each discrete step is given by energy preserving unitary transformation. We first verify laws of thermodynamics in such a paradigm, emphasizing the role of ergotropy. We then obtain analytically optimal efficiency and work production over all the minimal-coupling heat engines with single qubit working body and minimal number of strokes (i.e. three). One of our main tools is and object which we call control-marginal state. It acts only on the Hilbert space of the working body, but encapsulates all the features of the joint working body and battery system. Thanks to it in our optimization we can consider possible coherences as well as entanglement between working body and battery. 
CTP Quantum Information Days (online), 22-24 February 2021.
Center for Theoretical Physics PAS (Warsaw, Poland)