An unconventional method of continuous solid-state cryogenic cooling utilizing the electron subband degeneracy of semiconductor heterostructures is proposed in this Letter. An electrostatic heat pump is modeled, which employs subband "expansion" and "compression" to reach sub-dilution refrigeration temperatures with the fundamental limit set by electron-phonon interaction. Using an ultra-wide GaAs quantum well as an example, the cooling power per unit volume is estimated to reach 4.5mW/cm3 with a hot-side temperature of 300mK, suitable for applications such as quantum computers or infrared detectors.
@article{arxiv.2207.14237,
title = {Electron subband degeneracy heat pump for cryogenic cooling},
author = {Chulin Wang and Thomas Douglas and Matthew A Grayson},
journal= {arXiv preprint arXiv:2207.14237},
year = {2023}
}