Statistical electron excitation in a double quantum dot induced by two independent quantum point contacts

Gasser, U.; Gustavsson, S.; Küng, B.; Ensslin, K.; Ihn, T.; Driscoll, D. C.; Gossard, A. C.

Statistical electron excitation in a double quantum dot induced by two independent quantum point contacts

Authors

Description

We investigate experimentally the influence of current flow through two independent quantum point contacts to a nearby double quantum dot realized in a GaAs-AlGaAs heterostructure. The observed current through the double quantum dot can be explained in terms of coupling to a bosonic bath. The temperature of the bath depends on the power generated by the current flow through the quantum point contact. We identify the dominant absorption and emission mechanisms in a double quantum dot as an interaction with acoustic phonons. The experiment excludes coupling of a double quantum dot to shot noise generated by quantum point contact as the dominant mechanism.
9 pages, 7 figures