Condensed Matter Seminar Announcement Prof. Niels Gronbech-Jensen UC Davis, Department of Applied Science " Microwave induced features in low-temperature Josephson junctions -- switching distributions and Rabi oscillations " Date: Thursday, April 14, 2005 416 Phy/Geo Time: 4:10 pm. Abstract: We study analytically and numerically the phase-modulation properties of a biased classical Josephson tunnel junction in the zero-voltage state and phase-locked to an external ac field. We show that the phase-locked state is being modulated in the transients, or in response to perturbations, and the modulation frequency is calculated as a function of relevant system parameters, such as microwave field amplitude. The numerical analysis is parameterized similarly to recent experimental results in which a combination of pulsed ac signals and relative switching from the zero-voltage state are used to probe the internal excitations of the junctions. Our analysis demonstrates that the modulation of a phase-locked state in an entirely classical Josephson junction produces oscillations analogous to quantum mechanical Rabi oscillations, expected to be observed under the same conditions. We relate this study to our previous work on anomalous switching distributions in Josephson junction to assess the evidence for macroscopic quantum tunneling.

E-Mail: ngjensen@ucdavis.edu
Web Page: http://www.das.ucdavis.edu/