Abstract

We generalize the classical thermal Mpemba effect (where an
initially hot system relaxes faster to the final equilibrium state than
a cold one) to open quantum systems coupled to several reservoirs. We
show that, in general, two different types of quantum Mpemba effects are
possible. They may be distinguished by quantum state tomography.
However, the existence of a quantum Mpemba effect (without determining
the type) can already be established by measuring simpler observables
such as currents or energies. We illustrate our general results for the
experimentally feasible case of an interacting two-site Kitaev model
coupled to two metallic leads.