Gerhard Tulzer, Martin Hoffmann, Robert Zillich,
"Quantum heat engine based on dynamical materials design"
, in Physical Review B: Condensed Matter and Materials Physics, Vol. 102, Nummer 12, Seite(n) 125131, 9-2020, ISSN: 2469-9969
Original Titel:
Quantum heat engine based on dynamical materials design
Sprache des Titels:
Englisch
Original Kurzfassung:
We propose a quantum heat engine based on the ultrafast dynamical control of the magnetic properties of
a nanoscale working body. The working principle relies on nonlinear phononics, an example for dynamical
materials design. We describe the general recipe for identifying candidate materials, and also propose Cr 2 O 3
as a promising working body for a quantum Otto cycle. Using a spin Hamiltonian as a model for Cr 2 O 3 , we
investigate the performance in terms of efficiency, output power, and quantum friction. To assess the assumptions
underlying our effective spin Hamiltonian, we also consider a working substance composed of several unit
cells. We show that even without an implementation of transitionless driving, the quantum friction is very
low compared to the total produced work and the energy cost of counterdiabatic driving is negligible. This
is an advantage of the working substance, as experimentally hard-to-implement shortcuts to adiabaticity are
not needed. Moreover, we discuss some remarkable thermodynamic features due to the quantumness of the
proposed system such as a nonmonotonic dependence of the efficiency on the temperature of the hot bath.
Finally, we explore the dependence of the performance on the system parameters for a generic model of this type
of quantum heat engine and identify properties of the energy spectrum required for a well-performing quantum
heat engine.
Sprache der Kurzfassung:
Englisch
Journal:
Physical Review B: Condensed Matter and Materials Physics
Forschungs-