Phonon spectral density in a GaAs/AlGaAs double quantum dot
We study phonon emission in a GaAs/AlGaAs double quantum dot by monitoring the tunneling of a single electron between the two dots. We prepare the system such that a known amount of energy is emitted in the transition process. The energy is converted into lattice vibrations, and the resulting tunneling rate depends strongly on the phonon scattering and its effective phonon spectral density. We are