Quantum phase expectation values of a mesoscopic Josephson junction from quantum current measurements
INFM, Murst and Dipartimento di Scienze Fisiche ed
Astronomiche, Via Archirafi 36, 90123 Palermo, Italy
Published online: 15 July 2001
A simple way to acquire information on the mean values of the phase operators sinφ and cosφ of an ultrasmall Josephson junction prepared in an arbitrary pure or not state is reported. Our proposal exploits the recently predicted occurrence of current spikes in the I-V characteristic of a mesojunction irradiated by a quantum single-mode low-intensity coherent electromagnetic field. A necessary condition for the validity of our treatment is presented and discussed.
PACS: 73.23.-b – Electronic transport in mesoscopic systems. / 74.50.+r – Proximity effects, weak links, tunneling phenomena, and Josephson effects. / 42.50.Ct – Quantum description of interaction of light and matter; related experiments
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001