Evaporative Cooling in Semiconductor Devices

TL;DR

This paper explores a quantum-wire device mechanism for electron cooling via evaporative emission, showing potential for significant room-temperature electron cooling useful in optical detection.

Contribution

It introduces a model for electron cooling in solid-state devices through quantum filtering and re-equilibration, highlighting the impact of device geometry and experimental factors.

Findings

Significant electron cooling achievable at room temperature.

Device geometry influences final electron temperature.

Quantum effects enable cooling suitable for optical detection.

Abstract

We discuss the theory of cooling electrons in solid-state devices via ``evaporative emission.'' Our model is based on filtering electron subbands in a quantum-wire device. When incident electrons in a higher-energy subband scatter out of the initial electron distribution, the system equilibrates to a different chemical potential and temperature than those of the incident electron distribution. We show that this re-equilibration can cause considerable cooling of the system. We discuss how the device geometry affects the final electron temperatures, and consider factors relevant to possible experiments. We demonstrate that one can therefore substantial electron cooling due to quantum effects in a room-temperature device. The resulting cooled electron population could be used for photo-detection of optical frequencies corresponding to thermal energies near room temperature.