Nonequilibrium Steady States and MacLennan-Zubarev Ensembles in a Quantum Junction System

Based on a recent progress in nonequilibrium statistical mechanics of infinitely extended quantum systems, a nonequlibrium steady state (NESS) is constructed for a single-level quantum dot interacting with two free reservoirs under less general but more practically useful conditions than the previous works. As an example, a model of an Ahoronov-Bohm ring with a quantum dot is studied in detail. Then, NESS is shown to be regarded as a MacLennan-Zubarev ensemble. A formal relation between response and correlation at NESS is derived as well.Comment: submitted to Progress of Theoretical Physic

Analysis of magnetic characteristics of three-phase reactor made of grain-oriented silicon steel

Flux and iron loss distributions of three-phase reactor are analyzed using the finite element method considering 2-D B-H curves and iron losses in arbitrary directions which are measured up to high flux density. It is shown that the total iron loss of reactor yoke does not change so much by the yoke dimension, although the local iron loss is increased when the width of yoke is decreased. The experimental verification of flux and iron loss distributions are also carried out </p

Thermoelectric transport of perfectly conducting channels in two- and three-dimensional topological insulators

Topological insulators have gapless edge/surface states with novel transport properties. Among these, there are two classes of perfectly conducting channels which are free from backscattering: the edge states of two-dimensional topological insulators and the one-dimensional states localized on dislocations of certain three-dimensional topological insulators. We show how these novel states affect thermoelectric properties of the systems and discuss possibilities to improve the thermoelectric figure of merit using these materials with perfectly conducting channels.Comment: 10 pages, 6 figures, proceedings for The 19th International Conference on the Application of High Magnetic Fields in Semiconductor Physics and Nanotechnology (HMF-19

Evolutes of curves in the Lorentz-Minkowski plane

We can use a moving frame, as in the case of regular plane curves in the Euclidean plane, in order to define the arc-length parameter and the Frenet formula for non-lightlike regular curves in the Lorentz-Minkowski plane. This leads naturally to a well defined evolute associated to non-lightlike regular curves without inflection points in the Lorentz-Minkowski plane. However, at a lightlike point the curve shifts between a spacelike and a timelike region and the evolute cannot be defined by using this moving frame. In this paper, we introduce an alternative frame, the lightcone frame, that will allow us to associate an evolute to regular curves without inflection points in the Lorentz-Minkowski plane. Moreover, under appropriate conditions, we shall also be able to obtain globally defined evolutes of regular curves with inflection points. We investigate here the geometric properties of the evolute at lightlike points and inflection points