Role of d-wave pairing in A15A15 superconductors

We argue that the recent Raman spectroscopy observation of a sharp mode in s-wave superconducting V$_3$Si is due to a competing d-wave pairing state. We present microscopic arguments for the origin of this d-wave order. We further argue that the d-wave order explains the observed shrinking of the vortex core structure at anomalously low magnetic fields and the large anisotropy observed in the upper critical field

Test Data Sets for Evaluating Data Visualization Techniques

In this paper we take a step toward addressing a pressing general problem in the development of data visualization systems — how to measure their effectiveness. The step we take is to define a model for specifying the generation of test data that can be em-ployed for standardized and quantitative testing of a system’s per-formance. These test data sets, in conjunction with appropriate testing procedures, can provide a basis for certifying the effective-ness of a visualization system and for conducting comparative studies to steer system development

Low temperature resistivity of Ce‐La‐Th under pressure

The low temperature resistivity of Ce0.9-xLaxTh 0.1 alloys is known to vary as ρ0+αT 2. We have investigated the variation of ρ0 and α with pressure for several concentrations x. An unusually strong nonlinear decrease of the residual resistivity with pressure occurs; the magnitude of the decrease is an order-of-magnitude larger than in the isostructural nonmagnetic alloy La0.8Th0.2. The temperature coefficient α(P) also decreases strongly. These results are in qualitative accord with recent theories of the resistivity of disordered valence fluctuation compounds

Abstract

An antimagic labeling of a graph with m edges is a bijection λ from its edge set to {1, 2,...,m} such that the vertex sums are distinct, a vertex sum being the sum of the λ-values on the edges incident with the vertex. An antimagic graph is one that admits such a labeling. It was conjectured in [N. Hartsfield and G. Ringel, Supermagic and antimagic graphs, J. Recreational Math. 21 (1989), 107–115] that every connected graph other than K2 is antimagic. We verify this conjecture constructively for a class of graphs derived from the complete graphs Kn = (V, E) using a variant of magic squares. In support of our main result, we establish that Kn, with n ≥ 3, possesses a property stronger than being antimagic: for every function ω: V → N, there exists a such that the sums ω(v) + bijection λ: E → � 1, 2,..., � n 2 e∋v λ(e), for v ∈ V, are all different. This ‘robust ’ property of Kn proves useful in establishing that graphs of the form Kn − F, for certain F ⊂ E, are antimagic. Keywords: antimagic, latin square, magic square, RC-magic, transversal system 2000 MSC: Primary 05C78 Secondary 05C50, 05B1