On-chip quantum confinement refrigeration overcoming electron-phonon heat leaks

TL;DR

This paper demonstrates an on-chip cooling method using a 2DEG that significantly reduces electron temperatures, overcoming phonon heat leaks, and enabling potential microkelvin cooling for quantum devices.

Contribution

It introduces a novel 2DEG-based on-chip refrigeration technique that surpasses previous limitations imposed by phonon heat leaks.

Findings

Single-shot 2DEG cooler halves electron temperature

Hold time of up to one second achieved

Potential for continuous microkelvin cooling with arrays

Abstract

Circuit-based quantum devices rely on keeping electrons at millikelvin temperatures. Improved coherence and sensitivity as well as discovering new physical phenomena motivate pursuing ever lower electron temperatures, accessible using on-chip cooling techniques. Here we show that a two-dimensional electron gas (2DEG), manipulated using gate voltages, works as an on-chip heat sink only limited by a fundamental phonon heat-leak. A single-shot 2DEG cooler can reduce the electron temperature by a factor of two with a hold time up to a second. Integrating an array of such coolers to obtain continuous cooldown in will allow reaching down to microkelvin device temperatures.