Vendredi 20 janvier 2012, 11h
UMR 7335 CNRS–UNS, 1361 Route des Lucioles, Valbonne
L’Institut Non Linéaire de Nice vous invite au séminaire général de Physique avec :
Department of Mathematics and Physics, Catholic University, Brescia (Italy)
« Interplay of superradiance and disorder in coherent quantum transport »
Using an energy-independent non-Hermitian Hamiltonian approach to open systems, we fully describe transport through a sequence of potential barriers as external barriers are varied. Analyzing the complex eigenvalues of the non-Hermitian Hamiltonian model, a transition to a superradiant regime is shown to occur. The superradiance transition analyzed in our case is similar to the Dicke superradiance in quantum optics, but here the role of the ”photon bath” is played by the continuum of scattering states. Transport properties undergo a strong change at the superradiance transition, specifically maximum transmission is achieved at superradiance and a drastic change in the structure of resonances is demonstrated.
We then analyze higher dimensional systems where, as disorder is varied, different transport regimes can be explored : ballistic, diffusive and localized. We will analyze the interplay of disorder and degree of opening of the system in determining statistical properties of transport in mesoscopic systems.