Parts | Days | Selection | Search | Downloads | Help

DY: Dynamik und Statistische Physik

DY 24: Brownian Motion and Kinetic Theory I

DY 24.6: Talk

Tuesday, March 28, 2006, 15:45–16:00, H\"UL 186

High-efficiency Deterministic Josephson Vortex Ratchet — •Edward Goldobin¹, Markus Beck¹, Manfred Neuhaus², Michael Siegel², Reinhold Kleiner¹, and Dieter Koelle¹ — ¹Universität Tübingen, Physikalisches Institut - Experimentalphysik II, Auf der Morgenstelle 14, D-72076, Tübingen, Germany — ²Universität Karlsruhe, Institut für Mikro- und Nanoelektronische Systeme, Hertzstraße 16, 76187 Karlsruhe, Germany

We investigate experimentally a Josephson vortex ratchet — a fluxon in an asymmetric periodic potential driven by a deterministic force with zero time average. The highly asymmetric periodic potential is created in an underdamped annular long Josephson junction by means of a current injector providing an average velocity of the ac driven fluxon of up to 91% of the Swihart velocity. We measured the ratchet effect for driving forces with different spectral content. For monochromatic high-frequency drive the rectified voltage becomes quantized. At high driving frequencies we also observe chaos, sub-harmonic dynamics and voltage reversal due to the inertial mass of a fluxon.

[1] Phys. Rev. Lett. 95, 090603 (2005).