Probing the local temperature of a 2DEG microdomain with a quantum dot: measurement of electron-phonon interaction

TL;DR

This paper introduces a method to measure local electron temperature in a 2DEG microdomain using a quantum dot, revealing electron-phonon interactions and energy relaxation dynamics at subkelvin temperatures.

Contribution

The study presents a novel technique for local electron temperature detection via Coulomb-blockade peak analysis, providing new insights into electron-phonon coupling at low temperatures.

Findings

Electron-phonon energy flux scales with temperature to the fifth power.

Measured the coupling constant for electron-phonon interaction.

Demonstrated local temperature measurement using Coulomb blockade peaks.

Abstract

We demonstrate local detection of the electron temperature in a two-dimensionalmicrodomain using a quantum dot. Our method relies on the observation that a temperature bias across the dot changes the functional form of Coulomb-blockade peaks. We apply our results to the investigation of electron-energy relaxation at subkelvin temperatures, find that the energy flux from electrons into phonons is proportional to the fifth power of temperature, and give a measurement of the coupling constant.