Report

Quantum Limit of Heat Flow Across a Single Electronic Channel

See allHide authors and affiliations

Science  01 Nov 2013:
Vol. 342, Issue 6158, pp. 601-604
DOI: 10.1126/science.1241912

You are currently viewing the abstract.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

Quantum Heating

Mesoscopic wires exhibit peculiar properties at low temperatures. Their electric conductance can show plateaus at evenly spaced values, which reflects the sequential opening of “quantum transport channels,” each of which can only carry a finite amount of charge or heat. Whereas the step size for the electric conductance depends on the type of the particle carrying the charge, for heat conduction this “quantum” is universal. Jezouin et al. (p. 601, published online 3 October; see the Perspective by Sothmann and Flindt) measured the quantum of heat conduction through a single electronic channel by comparing the amount of heat needed to heat a small metal plate to a constant temperature, while varying the number of electronic channels through which the heat was dissipated from the plate. Encouragingly, the measurement was in agreement with the theoretical prediction.

Abstract

Quantum physics predicts that there is a fundamental maximum heat conductance across a single transport channel and that this thermal conductance quantum, GQ, is universal, independent of the type of particles carrying the heat. Such universality, combined with the relationship between heat and information, signals a general limit on information transfer. We report on the quantitative measurement of the quantum-limited heat flow for Fermi particles across a single electronic channel, using noise thermometry. The demonstrated agreement with the predicted GQ establishes experimentally this basic building block of quantum thermal transport. The achieved accuracy of below 10% opens access to many experiments involving the quantum manipulation of heat.

View Full Text