Asymptotic states in long Josephson junctions are investigated in an external magnetic field. We show that a choice one of the solution of the stationary Ferrell-Prange equation can carry be out with use of an asymptotic solution of the sine-Gordon equation and that an evolution to that stable solution occurs by passing through metastable states, which is determined with a form of quickly dampe...

We study the Josephson effect in chiral p-wave superconductor/diffusive normal metal DN /chiral p-wave superconductor CP/DN/CP junctions using quasiclassical Green’s function formalism with proper boundary conditions. The px+ ipy-wave symmetry of superconducting order parameter is chosen which is believed to be the pairing state in Sr2RuO4. We show that the superconducting pair amplitude induce...

We analyze a controllable generation of maximally entangled mixed states of a circuit containing two-coupled superconducting charge qubits. Each qubit is based on a Cooper pair box connected to a reservoir electrode through a Josephson junction. Illustrative variational calculations were performed to demonstrate the effect on the two-qubits entanglement. At sufficiently deviation between the Jo...

Superconductivity derives its most salient features from the coherence of the associated macroscopic wave function. The related physical phenomena have now moved from exotic subjects to fundamental building blocks for quantum circuits such as qubits or single photonic modes. Here we predict that the a.c. Josephson effect-which transforms a d.c. voltage Vb into an oscillating signal cos (2eVbt/ħ...

A Josephson junction, consisting of two superconductors weakly coupled together, is an example of a very simple macroscopic quantum system. When there is a voltage V across the junction, the supercurrents flowing through it oscillate at a frequency given very precisely by the relation v=2eVlh. The general validity of this formula has been used recently by Parker, Langenberg, Denenstein, and Tay...

We study the Josephson effect through a quantum dot magnet whose spin is isotropic and which is coupled to the dot electron spin via exchange coupling. We calculate the Andreev levels and the supercurrent and examine the intertwined effect of the exchange coupling, Kondo correlation, and superconductivity. The former suppresses Kondo correlations, which triggers phase transitions from the 0 to ...

In this paper we consider the Rapid Single-Flux Quantum (RSFQ) circuits with reduced Josephson current density and especially deal with one of the basic building blocks of these electronics the DC to SFQ converter. For future promising RSFQ applications the critical current of the Josephson junctions should be reduced (by reduction of Josephson current density) to several μA, resulting into val...