title: Intrinsic Metastabilities in the Charge Configuration of a Double Quantum Dot.
abstract: We report a thermally activated metastability in a GaAs double quantum dot exhibiting real-time charge switching in diamond shaped regions of the charge stability diagram. Accidental charge traps and sensor backaction are excluded as the origin of the switching. We present an extension of the canonical double dot theory based on an intrinsic, thermal electron exchange process through the reservoirs, giving excellent agreement with the experiment. The electron spin is randomized by the exchange process, thus facilitating fast, gate-controlled spin initialization. At the same time, this process sets an intrinsic upper limit to the spin relaxation time.
authors.affiliation: Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland.
authors.forename: D E F
authors.initials: DE
authors.lastname: Biesinger
authors.affiliation: Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland.|Swiss Federal Laboratories for Materials Science and Technology, EMPA, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.
authors.forename: C P
authors.initials: CP
authors.lastname: Scheller
authors.affiliation: Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom.
authors.forename: B
authors.initials: B
authors.lastname: Braunecker
authors.affiliation: Materials Department, University of California, Santa Barbara, California 93106, USA.
authors.forename: J
authors.initials: J
authors.lastname: Zimmerman
authors.affiliation: Materials Department, University of California, Santa Barbara, California 93106, USA.
authors.forename: A C
authors.initials: AC
authors.lastname: Gossard
authors.affiliation: Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland.
authors.forename: D M
authors.initials: DM
authors.lastname: Zumbühl