Quantization of Heat Flow in Fractional Quantum Hall States

Quantum mechanics sets an upper bound on the amount of charge flow as well as on the amount of heat flow in ballistic one-dimensional channels. The two relevant upper bounds, that combine only fundamental constants, are the quantum of the electrical conductance, Ge=e^2/h, and the quantum of the thermal conductance, Gth=π^2k_B^2T/3h. Remarkably, the latter does not depend on particles charge; particles exchange statistics; and even the interaction strength among the particles.

However, unlike the relative ease in determining accurately the quantization of the electrical conductance, measuring accurately the thermal conductance is more challenging.