Regensburg 2007 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

DY: Fachverband Dynamik und Statistische Physik

DY 8: Quantum dynamics, decoherence and quantum information

DY 8.2: Vortrag

Montag, 26. März 2007, 16:30–16:45, H2

Dephasing by non-Gaussian shot noise in an electronic which-path experiment — •Florian Marquardt¹, Izhar Neder², and Mordehai Heiblum² — ¹Arnold Sommerfeld Center for Theoretical Physics, Department für Physik, und Center for NanoScience, Ludwig-Maximilians-Universität München, Germany — ²Braun Center for Submicron Research, Department of Condensed Matter Physics, Weizmann institute, Rehovot, Israel

The usual models for dissipative environments involve a bath of harmonic oscillators, producing Gaussian fluctuations. However, modern experiments on dephasing in qubits and electronic interferometers indicate strong coupling to non-Gaussian quantum noise. Most strikingly, the coherence (interference contrast) may oscillate as a function of interaction time and other control parameters (such as detector voltage). We discuss in detail the theory behind a recent "controlled dephasing" experiment involving a Mach-Zehnder interferometer strongly coupled to the non-Gaussian shot noise of a detector edge channel [cond-mat/0610634,cond-mat/0611372].