Single Cooper-pair tunnelling induced by non-classical microwaves
Department of Applied Physics, Delft University of Technology, 2628 CJ Delft, The
and Nuclear Physics Institute, Moscow State University, Moscow 119899 GSP, Russia
2 Department of Electrical Engineering and Electronics, The University of Liverpool, Brownlow Hill, PO Box 147, Liverpool L69 3BX, England
Accepted: 21 March 1996
A mesoscopic Josephson junction interacting with a mode of non-classical microwaves with frequency ω is considered. Squeezing of the electromagnetic field drastically affects the dynamics of Cooper tunnelling. In particular, Bloch steps can be observed even when the microwaves are in the squeezed vacuum state with zero average amplitude of the field . The interval between these steps is double in size in comparison to the conventional Bloch steps.
PACS: 73.40.Gk – Tunneling / 74.50.+r – Proximity effects, weak links, tunnelling phenomena, and Josephson effects / 42.50.Dv – Nonclassical field states; squeezed, antibunched, and sub-Poissonian states; operational definitions of the phase of the field; phase measurements
© EDP Sciences, 1996