Relation Between Local Temperature Gradients and the Direction of Heat   Flow in Quantum Driven Systems
  We introduce thermometers to define the local temperature of an electronic system driven out-of-equilibrium by local ac fields. We discuss the behavior of the local temperature along the sample, showing that it exhibits spatial fluctuations following an oscillatory pattern. We show explicitly that the local temperature is the correct indicator for heat flow. 
Alvaro Caso, Liliana Arrachea, Gustavo S. Lozano
cond-mat.mes-hall