120,757 research outputs found
On the Casimir effect for parallel plates in the spacetime with one extra compactified dimension
In this paper, the Casimir effect for parallel plates in the presence of one
compactified universal extra dimension is reexamined in detail. Having
regularized the expressions of Casimir force, we show that the nature of
Casimir force is repulsive if the distance between the plates is large enough,
which is disagree with the experimental phenomena.Comment: 7 pages, 3 figure
Intrinsic Spin Hall Effect in the Two Dimensional Hole Gas
We show that two types of spin-orbit coupling in the 2 dimensional hole gas
(2DHG), with and without inversion symmetry breaking, contribute to the
intrinsic spin Hall effect\cite{murakami2003,sinova2003}. Furthermore, the
vertex correction due to impurity scattering vanishes in both cases, in sharp
contrast to the case of usual Rashba coupling in the electron band. Recently,
the spin Hall effect in a hole doped semiconductor has been observed
experimentally by Wunderlich \emph{et al}\cite{wunderlich2004}. From the fact
that the life time broadening is smaller than the spin splitting, and the fact
impurity vertex corrections vanish in this system, we argue that the observed
spin Hall effect should be in the intrinsic regime.Comment: Minor typos fixed, one reference adde
Statistical variability and reliability in nanoscale FinFETs
A comprehensive full-scale 3D simulation study of statistical variability and reliability in emerging, scaled FinFETs on SOI substrate with gate-lengths of 20nm, 14nm and 10nm and low channel doping is presented. Excellent electrostatic integrity and resulting tolerance to low channel doping are perceived as the main FinFET advantages, resulting in a dramatic reduction of statistical variability due to random discrete dopants (RDD). It is found that line edge roughness (LER), metal gate granularity (MGG) and interface trapped charges (ITC) dominate the parameter fluctuations with different distribution features, while RDD may result in relatively rare but significant changes in the device characteristics
Cointegrating Rank Selection in Models with Time-Varying Variance
Reduced rank regression (RRR) models with time varying heterogeneity are considered. Standard information criteria for selecting cointegrating rank are shown to be weakly consistent in semiparametric RRR models in which the errors have general nonparametric short memory components and shifting volatility provided the penalty coefficient C_{n}-> infinity and C_{n}/n -> 0 as n -> infinity. The AIC criterion is inconsistent and its limit distribution is given. The results extend those in Cheng and Phillips (2008) and are useful in empirical work where structural breaks or time evolution in the error variances is present. An empirical application to exchange rate data is provided.Cointegrating rank, Consistency, Heterogeneity, Information criteria, Model selection, Nonparametric, Time varying variances, Unit roots
Coexistence and competition of multiple charge-density-wave orders in rare-earth tri-telluride RTe3
The occurrences of collective quantum states, such as superconductivity (SC)
and charge- or spin-densitywaves (CDWs or SDWs), are among the most fascinating
phenomena in solids. To date much effort has been made to explore the interplay
between different orders, yet little is known about the relationship of
multiple orders of the same type. Here we report optical spectroscopy study on
CDWs in the rare-earth tri-telluride compounds RTe3 (R = rare earth elements).
Besides the prior reported two CDW orders, the study reveals unexpectedly the
presence of a third CDW order in the series which evolves systematically with
the size of R element. With increased chemical pressure, the first and third
CDW orders are both substantially suppressed and compete with the second one by
depleting the low energy spectral weight. A complete phase diagram for the
multiple CDW orders in this series is established.Comment: 7 pages, 4 figures, 1 tabl
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