A quantum-dot refrigerator

Abstract

A cryogenic refrigeration scheme is presented which utilizes the discrete energy levels of quantum dots to customize the electronic Fermi–Dirac distribution, cooling a small but macroscopic reservoir to far below the ambient temperature. Several physical limitations of this scheme are discussed within the context of a model device constructed from a two-dimensional electron gas. These are explored in a simple example where, at an ambient operating temperature of 150 mK, this quantum-dot refrigerator can achieve a cooling power of 1 μW/cm2, a base temperature of 10 mK, and a cooling efficiency of 35%.