https://doi.org/10.1140/epjb/e2003-00098-2
Vortices in Josephson arrays interacting with non-classical microwaves: The effect of dissipation
1
Department of Computing, University of Bradford,
Bradford BD7 1DP, UK
2
Department of Electrical Engineering and Electronics,
University of Liverpool, Liverpool L69 3GJ, UK
3
School of Engineering and Information Technology,
University of Sussex, Falmer, Brighton BN1 9QT, UK
Corresponding author: a a.konstadopoulou@brad.ac.uk
Received:
21
October
2002
Revised:
11
February
2003
Published online:
11
April
2003
Vortices circulating in a ring made from a Josephson array in the insulating phase are studied. The ring contains a `dual Josephson junction' through which the vortices tunnel. External non-classical microwaves are coupled to the device. The time evolution of this two-mode fully quantum mechanical system is studied, taking into account the dissipation in the system. The effect of the quantum statistics of the photons on the quantum statistics of the vortices is discussed. Entropic calculations quantify the entanglement between the two systems. Quantum phenomena in the system are also studied through Wigner functions. After a certain time (which depends on the dissipation parameters) these quantum phenomena are destroyed due to dissipation.
PACS: 74.50.+r – Tunneling phenomena; point contacts, weak links, Josephson effects / 85.25.Dq – Superconducting quantum interference devices (SQUIDs) / 42.50.Dv – Nonclassical states of the electromagnetic field, including entangled photon states; quantum state engineering and measurements
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2003
