24,637 research outputs found
Comment On >Assessment Of Field-Induced Quantum Confinement In Heterogate Germanium Electron-Hole Bilayer Tunnel Field-Effect Transistor> Appl. Phys. Lett. 105, 082108 (2014)
Not AvailableNRI SWAN
programNSF NASCENT ERCMicroelectronics Research CenterElectrical and Computer Engineerin
Avalanche-Induced Current Enhancement in Semiconducting Carbon Nanotubes
Semiconducting carbon nanotubes under high electric field stress (~10 V/um)
display a striking, exponential current increase due to avalanche generation of
free electrons and holes. Unlike in other materials, the avalanche process in
such 1D quantum wires involves access to the third sub-band, is insensitive to
temperature, but strongly dependent on diameter ~exp(-1/d^2). Comparison with a
theoretical model yields a novel approach to obtain the inelastic optical
phonon emission length, L_OP,ems ~ 15d nm. The combined results underscore the
importance of multi-band transport in 1D molecular wires
MAGIC observations of Mkn 421 in 2008, and related optical/X-ray/TeV MWL study
The HBL-type blazar Markarian 421 is one of the brightest TeV gamma-ray
sources of the Northern sky. From December 2007 until June 2008 it was
intensively observed in the VHE (E>100 GeV) band by the MAGIC gamma-ray
telescope. The source showed intense and prolonged activity during the whole
period. In some nights the integral flux rose up to 3.6 Crab units (E>200 GeV).
Intra-night rapid flux variations were observed. We compared the optical (KVA)
and X-ray (RXTE-ASM, Swift-XRT) data with the MAGIC VHE data, investigating the
correlations between different energy bands.Comment: 4 pages,4figures, Contribution to the 31st ICRC, Lodz, Poland, July
200
Counting fermionic zero modes on M5 with fluxes
We study the Dirac equation on an M5 brane wrapped on a divisor in a
Calabi--Yau fourfold in the presence of background flux. We reduce the
computation of the normal bundle U(1) anomaly to counting the solutions of a
finite--dimensional linear system on cohomology. This system depends on the
choice of flux. In an example, we find that the presence of flux changes the
anomaly and allows instanton corrections to the superpotential which would
otherwise be absent.Comment: 14 pages. v2: reference added, typos corrected, few change
Average-Case Optimal Approximate Circular String Matching
Approximate string matching is the problem of finding all factors of a text t
of length n that are at a distance at most k from a pattern x of length m.
Approximate circular string matching is the problem of finding all factors of t
that are at a distance at most k from x or from any of its rotations. In this
article, we present a new algorithm for approximate circular string matching
under the edit distance model with optimal average-case search time O(n(k + log
m)/m). Optimal average-case search time can also be achieved by the algorithms
for multiple approximate string matching (Fredriksson and Navarro, 2004) using
x and its rotations as the set of multiple patterns. Here we reduce the
preprocessing time and space requirements compared to that approach
Effect of Particle Orientation on the Elastic Anisotropy of Al/SiCp Metal Matrix Composites
Metal matrix composites (MMCs) are promising new materials for structural applications because of their high specific stiffness and strength, and high temperature stability. Of particular interest are the discontinuous silicon carbide (SiC) reinforced aluminum metal matrix composites. The improved mechanical properties are governed by the properties of the constituent phases, as well as the SiC particle characteristics such as shape, aspect ratio and orientation. The particle characteristics have a major effect on the anisotropic properties of these composites. The overall properties also depend on the manufacturing process of these composites since it determines the orientation of the particles and may produce internal defects such as porosity and intermetallic compounds [l]. Thus it is important to experimentally characterize the effective elastic properties and to theoretically predict them from the knowledge of the constituent properties and the microstructures
Long term monitoring of bright TeV Blazars with the MAGIC telescope
The MAGIC telescope has performed long term monitoring observations of the
bright TeV Blazars Mrk421, Mrk501 and 1ES1959+650. Up to 40 observations, 30 to
60 minutes each have been performed for each source evenly distributed over the
observable period of the year. The sensitivity of MAGIC is sufficient to
establish a flux level of 25% of the Crab flux for each measurement. These
observations are well suited to trigger multiwavelength ToO observations and
the overall collected data allow an unbiased study of the flaring statistics of
the observed AGNs.Comment: 4 pages, 4 figures, to appear in the proceedings of the 30th
International Cosmic Ray Conference, Merida, July 200
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