In the electroweak sector of the standard model topologically inequivalent vacua are separated by finite energy barriers, whose height is given by the sphaleron. For large values of the Higgs mass there exist several sphaleron solutions and the barriers are no longer symmetric. We construct paths of classical configurations from one vacuum to a neighbouring one and solve the fermion equations i...

Directed graphs are commonly drawn by a four phase framework introduced by Sugiyama et al. in 1981. The vertices are placed on parallel horizontal levels. The edge routing between consecutive levels is computed by solving one-sided 2-level crossing minimization problems, which are repeated in up and down sweeps over all levels. Crossing minimization problems are generally NP-hard. We introduce ...

Helium nanodroplet isolation is used to produce van der Waals-bound quartet state alkali trimers ~Na3 and K3! selectively over the corresponding chemically bound doublet trimers. Frequency-resolved excitation and emission spectroscopy reveals the presence of nonadiabatic spin–flip processes in the electronically excited states. A total of four quartet to quartet electronic transitions are obser...

Atomic avoided crossings in strong magnetic and electric fields are usually identified by the energy level repulsion and by the sharp extremal value of the Shannon’s entropy of the two involved states. In this work the proposal of a new information-theoretic parameter, the continuous Fisher information, for the prediction and characterization of these nonlinear phenomena is done. For just aroun...

We discuss adiabatic quantum phenomena at a level crossing. Given a path in the parameter space which passes through a degeneracy point, we find a criterion which determines whether the adiabaticity condition can be satisfied. For paths that can be traversed adiabatically we also derive a differential equation which specifies the time dependence of the system parameters, for which transitions b...

The coexistence of π-flux state and d-wave RVB state is considered in this paper within the slave boson approach. A critical value of doping concentration δc is found, below which the coexisting π-flux and d-wave RVB state is favored in energy. The pseudo Fermi surface of spinons and the physical electron spectral function are calculated. A clear Fermi-level crossing is found along the (0,0) to...