120 research outputs found
Nonequilibrium transport and statistics of Schwinger pair production in Weyl semimetals
The non-equilibrium dynamics beyond linear response of Weyl semimetals is
studied after a sudden switching on of a DC electric field. The resulting
current is a nonmonotonic function of time, with an initial quick increase of
polarization current followed by a power-law decay. Particle-hole creation \`a
la Schwinger dominates for long times when the conduction current takes over
the leading role, with the total current increasing again. The conductivity
estimated from a dynamical calculation within a Drude picture agrees with the
one obtained from Kubo's formula. The full distribution function of
electron-hole pairs changes from Poissonian for short perturbations to a
Gaussian in the long perturbation (Landau-Zener) regime. The vacuum persistence
probability of high energy physics manifests itself in a finite probability of
no pair creation and no induced current at all times.Comment: 7 pages, 4 figure
Analytical drainâcurrent model of pâ and nâchannel OTFTs for circuit simulation
Organic thin-film transistors (OTFTs) are an emerging technology for large scale circuit integration, owing the availability of both p- and n- channel devices. For the technology development and the design of circuits and digital systems, the accurate physical modeling is mandatory. In this work we propose an unified analytical model for both p- and n- type OTFTs. The model is physically based and accounts for a double exponential density of states (DOS). It is simple, symmetric and accurately describes the below-threshold, linear, and saturation regimes via a unique formulation. The model is eventually validated with the measurements of complementary OTFTs fabricated in a fullyprinted technolog
Dynamics of conflicts in Wikipedia
In this work we study the dynamical features of editorial wars in Wikipedia
(WP). Based on our previously established algorithm, we build up samples of
controversial and peaceful articles and analyze the temporal characteristics of
the activity in these samples. On short time scales, we show that there is a
clear correspondence between conflict and burstiness of activity patterns, and
that memory effects play an important role in controversies. On long time
scales, we identify three distinct developmental patterns for the overall
behavior of the articles. We are able to distinguish cases eventually leading
to consensus from those cases where a compromise is far from achievable.
Finally, we analyze discussion networks and conclude that edit wars are mainly
fought by few editors only.Comment: Supporting information adde
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