Switching Current of a Cooper Pair Transistor with Tunable Josephson Junctions
2002 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 66, no 1, 14510- p.Article in journal (Refereed) Published
We investigate the switching current of a Cooper pair transistor with tunable Josephson energy. The junctions are fabricated in a superconducting quantum interference device (SQUID) geometry which allows for an in situ tunable effective Josephson energy by application of a magnetic field. We find a 2e-periodic switching current versus gate charge. As the magnetic field is increased the switching current stays 2e-periodic but the magnitude is suppressed. At a magnetic field of half a flux quantum through the SQUID's the switching current is minimum. We can theoretically model the experimental data by assuming a switching current which is proportional to the ideal critical current squarred. We show that such a dependence is expected in the limit where the effect of thermal fluctuations on the system is strong.
Place, publisher, year, edition, pages
2002. Vol. 66, no 1, 14510- p.
single-electron transistor, bloch transistors, periodicity, 2e
IdentifiersURN: urn:nbn:se:kth:diva-6279DOI: 10.1103/PhysRevB.66.014510ISI: 000177284900124OAI: oai:DiVA.org:kth-6279DiVA: diva2:10952
QC 201009242006-10-232006-10-232010-09-24Bibliographically approved