Open quantum rotors: Connecting correlations and physical currents

We consider a finite one-dimensional chain of quantum rotors interacting with a set of thermal baths at different temperatures. When the interaction between the rotors is made chiral, such a system behaves as an autonomous thermal motor, converting heat currents into nonvanishing rotational ones. Such a dynamical response is strongly pronounced in the range of the Hamiltonian parameters for which the ground state of the system in the thermodynamic limit exhibits a quantum phase transition. Such working points are associated with large quantum coherence and multipartite quantum correlations within the state of the system. This suggests that the optimal operating regime of such a quantum autonomous motor is one of maximal quantumness.

Automated summary

We investigate the interaction between a finite one-dimensional chain of quantum rotors and thermal baths at different temperatures. When the interaction between the rotors is made chiral, the system acts as an autonomous thermal motor, converting heat currents into nonvanishing rotational ones. This behavior is strongly pronounced when the system undergoes a quantum phase transition in the ground state. The optimal operating regime of such a quantum autonomous motor is associated with large quantum coherence and multipartite quantum correlations within the state of the system.