The projection-like techniques for Wigner's distribution function

Roberto M. Serra, N. G. de Almeida, Celso J. Villas-Bôas +1 more

We propose a reliable scheme for engineering a general cavity-field state. This is different from recently presented strategies, where the cavity is supposed to be initially empty and the field is built up photon by photon through resonant atom-field interactions. Here, a coherent state is previously injected into the cavity. So, the Wigner distribution function of the desired state is constructed from that of the initially coherent state. Such an engineering process is achieved through an adaptation of the recently proposed technique of projection synthesis to cavity QED phenomena.

M. Revzen

M. H. S. Amin, Evgeny V. Bezuglyi, Kijko, A.S. +1 more

A technique for studying collisionless dynamics of a homogeneous superconducting system is \ndeveloped which is based on Riccati parametrization of the Wigner distribution function. The \nquantum evolution of the superconducting order parameter, initially deviating from the equilibrium \nvalue, is calculated using this technique. The effect of a time-dependent BCS paring \ninteraction on the dynamics of the order parameter is also studied.

GERALD J. IAFRATE, H. L. Grubin, David K. Ferry

Joachim J. Włodarz

M. H. S. Amin, E. V. Bezuglyi, A. S. Kijko +1 more

A technique for studying collisionless dynamics of a homogeneous superconducting system is developed which is based on Riccati parametrization of the Wigner distribution function. The quantum evolution of the superconducting order parameter, initially deviating from the equilibrium value, is calculated using this technique. The effect of a time-dependent BCS paring interaction on the dynamics of the order parameter is also studied.