DPG Phi
Verhandlungen
Verhandlungen
DPG

Dresden 2011 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 46: SC: Tunneling, Josephson Junctions, SQUIDs 1

TT 46.2: Talk

Thursday, March 17, 2011, 10:45–11:00, HSZ 301

Dependence of the macroscopic quantum tunneling rate on Josephson junction area — •Roland Schäfer1,2, Christoph Kaiser3, and Michael Siegel2,31Institut für Festkörperphysik, Karlsruhe Instituteof Technology, 76021 Karlsruhe — 2Center for Functional Nanostructures, 76128 Karlsruhe — 3Institut für Mikro- und Nanoelektronische Systeme, Karlsruhe Institute of Technology, 76187 Karlsruhe

We have carried out systematic Macroscopic Quantum Tunneling (MQT) experiments on Nb/Al-AlOx/Nb Josephson junctions (JJs) of different areas. Employing on-chip lumped element inductors, we have decoupled the JJs from their environmental line impedances at the frequencies relevant for MQT. This allowed us to study the crossover from the thermal to the quantum regime in the low damping limit. A clear reduction of the crossover temperature with increasing JJ size is observed and found to be in accord with theory. Deviations of the observed quantum rate from theoretical predictions are thoroughly analized and discussed in the framework of Kramer’s [1] turnover problem.
H. A. Kramers, Physica (Utrecht), 7, 284 (1940).

100% | Mobile Layout | Deutsche Version | Contact/Imprint/Privacy
DPG-Physik > DPG-Verhandlungen > 2011 > Dresden