Where Zitterbewegungen may lead

Richard Berkovits

A new application of the density matrix renormalization group (DMRG) method to a system composed of an interacting dot coupled to a infinite one dimensional lead is presented. This method enables one to study the influence of the coupling to an external lead on the thermodynamical properties of the dot. It is shown that this method reproduces known results for a non-interacting dot coupled to a lead, i.e., that for strong coupling discrete states remain in the dot. We show that these states are robust and do not disappear once interactions in the dot are considered. Moreover, due to these discrete states, Coulomb blockade affects the charging of the dot even though its strongly coupled to a lead.

Saul T. Epstein

Qihong Lou, Hongping Guo, Yunsheng Huo

Raman energy-conversion efficiency in lead vapour as high as 52% was obtained with a pumping XeCl excimer laser used in an unstable-resonator configuration. The characteristics of stimulated Raman scattering in lead vapour pumped by the XeCl laser with unstable and stable resonators were compared in detail. Relaxation oscillations of the Raman-shifted pulse were observed, and these are related to the effect of ground-state depletion of atoms in the lead vapour.

David Hestenes

Minglin Jin

The nonresonant multiphoton ionization process of lead atoms are investigated at the laser wavelengths of 1064 nm, 532 nm, 355 nm. The dependence of the 7-photon ionization probability of lead atoms on the statistical properties of laser pulse has been analysed by varying the spectral bandwidth of the laser pulse.