On dephasing and spin decay in open quantum dots

Abstract

The thesis contains three topics on transport in nanostructres. Chpt. 2 explains the loss of entanglement in electronic pairs that enter chaotic quantum dots. The quantitiy that is affected are timedependent and spaceresolving current measurements. Looking at statisticcs dots, it is discovered that there the vulnerability of the entanglement between electron pairs with respect to dephasing depends on the presence of magnetic fields and is usually seveer. A test for total loss of entanglement is formulated by means of spin resolving noise correlators.Chpt. 3 postulates the extension of a model for inelastic scattering to descibe that there is a temperature rang in which weak localization is not present but shot noise well measureable. The model relies on the use of of diagramatic expansions within random matrix theory. Chapt. 4 and 5 consider a tripple quantum dots in which despite an applied voltage and despite levels in that voltage window, the current is suppressed to zero. This is diminished by couplings to phonons. It is found that couting of individual electrons on such a multi dot structure should lead to dephasing dependent statistics. Chpt. 5 shows how dipole selection rules affect the entanglement transport from band Electrons to photons.