We show that the absolutely continuous part of the spectral function of the one-dimensional Dirac operator on a half-line with a constant mass term and a real, square-integrable potential is strictly increasing throughout the essential spectrum (−∞,−1] ∪ [1,∞). The proof is based on estimates for the transmission coefficient for the full-line scattering problem with a truncated potential and a ...

We measure low temperature current transport properties of superconducting Sn contacts to pf-GaAs. For contacts alloyed at 450 C, the current-voltage characteristics show a strong dependence on alloying time. The critical temperature of Sn near the superconductor-semiconductor interface decreases from 3.8 to 1.8 K as the alloying time increases from 0 to 120 s. On the other hand, a long-time al...

This paper describes an efficient algorithm for the design of lattice wave digital filters with short coefficient wordlength. The proposed algorithm guarantees that the optimum finitewordlength solution can be found for both the fixed-point and the multiplierless coefficient representations. This is illustrated by means of several examples.

ABSTRACT We present a calculation of the rare decay mode D0 → γγ, in which the long distance contributions are expected to be dominant. Using the Heavy Quark Chiral Lagrangian with a strong g coupling as recently determined by CLEO from the D∗ → Dπ width, we consider both the anomaly contribution which relates to the annihilation part of the weak Lagrangian and the one-loop π, K diagrams. The l...

The angular and frequency correlation functions of the transmission coefficient for light propagation through a strongly scattering amplifying medium are considered. It is found that just as in the case of an elastic scattering medium the correlation function consists of three terms. However, the structure of the terms is rather different. Angular correlation has a power-law decay and exhibits ...

ABSTRACT We present a calculation of the rare decay mode D0 → γγ, in which the long distance contributions are expected to be dominant. Using the Heavy Quark Chiral Perturbation Theory Lagrangian with a strong g coupling as recently determined by CLEO from the D∗ → Dπ width, we consider both the anomaly contribution which relates to the annihilation part of the weak Lagrangian and the one-loop ...

Veselago medium (also called double negative material, backward medium, left-handed medium) is a medium with both negative isotropic dielectric permittivity and permeability. It has the effect of backward waves with negative (anomalous) refraction, in contrast to the usual forward waves with normal refraction in normal isotropic dielectrics and/or magnetics. In this paper, examples of the exist...

P.A. Martin / Wave Motion 51 (2014) 296–307 297 transmission coefficient is calculated exactly, as is the average transmission coefficient. These results do not assume that ε is small (compared to the spacing or wavelength) but they are complicated. We then approximate these results for small kε, and we show that they can be obtained more easily by assuming that kε is small from the outset. Thi...

We study the dynamics of the classical and quantum mechanical scattering of a wave packet from an oscillating barrier. Our main focus is on the dependence of the transmission coefficient on the initial energy of the wave packet for a wide range of oscillation frequencies. The behavior of the quantum transmission coefficient is affected by tunneling phenomena, resonances, and kinematic effects e...

This chapter considers the problem of data gathering in correlated wireless sensor networks with distributed source coding (DSC), and virtual multiple input and multiple output (MIMO) based cooperative transmission. Using the concepts of super and sub modularity on a lattice, we analytically quantify as how the optimal constellation size, and optimal number of cooperating nodes, vary with respe...