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

摘要

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