  Unveiling the impact in thermodynamics of the phenomena specific to quantum
mechanics is a crucial step to identify fundamental costs for quantum
operations and quantum advantages in heat engines. We propose a two-reservoir
setup to detect the quantum component in the heat flow exchanged by a
coherently driven atom with its thermal environment. Tuning the driving
parameters switches on and off the quantum and classical contributions to the
heat flows, enabling their independent characterization. We demonstrate the
feasibility of the measurement in a circuit-QED setup. Our results pave the
road towards the first experimental verification of this quantum thermodynamic
signature ubiquitous in quantum technologies.
