6,088,617 research outputs found
Formation of Magnetic Monopoles in Hot Gauge Theories
In this talk, I discuss the formation of magnetic monopoles in a phase
transition from the confining SU(2) phase to the Coulomb phase in a hot
Georgi-Glashow model. I argue that monopoles are formed from long-wavelength
thermal fluctuations, which freeze out after the phase transition.Comment: 5 pages, talk given at Strong and Electroweak Matter 2002,
Heidelberg, October 2-5, 200
Global Phase Diagram of Disordered Type-II Weyl Semimetals
With electron and hole pockets touching at the Weyl node, type-II Weyl
semimetal is a newly proposed topological state distinct from its type-I
cousin. We numerically study the localization effect for tilted type-I as well
as type-II Weyl semimetals and give the global phase diagram. For dis- ordered
type-I Weyl semimetal, an intermediate three-dimensional quantum anomalous Hall
phase is confirmed between Weyl semimetal phase and diffusive metal phase.
However, this intermediate phase is absent for disordered type-II Weyl
semimetal. Besides, near the Weyl nodes, comparing to its type-I cousin,
type-II Weyl semimetal possesses even larger ratio between the transport
lifetime along the direction of tilt and the quantum lifetime. Near the phase
boundary between the type-I and the type-II Weyl semimetals, infinitesimal
disorder will induce an insulating phase so that in this region, the concept of
Weyl semimetal is meaningless for real materials.Comment: 7 pages, 5 figure
LOW-COST REMOTE WEATHER INFORMATION SYSTEM PHASE I AND PHASE 2
Remote Weather Information Systems (RWIS) are an important part of deciding maintenance activities and scheduling. However, the cost of RWIS limits the number of systems that can be deployed. Because of the lack of power and the high power budget of commonly used systems, some locations are not suitable for RWIS even though the information would be of great value. This project focuses on the development of a low-cost, low-power RWIS that is suitable for remote locations and allows for a higher density of RWIS. The system produced under this study uses less than 10 watts of power and costs less than $10,000 for the basic system. The system has performed well in Fairbanks, Alaska, over two winters. In addition, the system has been fully integrated into the Alaska Department of Transportation and Public Facilities RWIS network.WeatherCloud Inc
Exact cascading nonlinearity in quasi-phase-matched quadratic media
The evolution of light pulses and beams in a quasi-phase-matched (QPM)
quadratic medium is usually described by considering only the spatial harmonic
of the QPM grating that minimizes the residual phase-mismatch. I show that, for
strongly phase-mismatched interactions (the cascading regime), several
harmonics need to be accounted for in order to obtain the correct value of the
effective cubic nonlinearity, of which I find a simple analytical expression. I
discuss the effects of the higher order harmonics of the grating on solitary
wave propagation
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