Carrier decay transients in 4H-SiC n-type and p-type epilayers have been characterized using a non-destructive, non-contact microwave photoconductivity technique. Decay transients show a two-stage exponential decay with first decay constants as high as 400 ns in 10 μm p-type epilayers. The second decay constant increases with temperature and is dominated by interface recombination.

The influence of exponential magnetic field decay (MFD) on the spin evolution of isolated neutron stars is studied. The ROSAT observations of several X-ray sources, which can be accreting old isolated neutron stars, are used to constrain the exponential and power-law decay parameters. We show that for the exponential decay the ranges of minimum value of magnetic moment, μb, and the characterist...

Transient signals naturally arise in numerous disciplines for which the decay rates and amplitudes carry some informational significance. Even when the decay rates are known, solving for the amplitudes results in an ill-conditioned formulation. Transient signals in the presence of noise are further complicated as the signal-to-noise ratio asymptotically decreases in time. In this thesis the Dis...

Abstract We show that the components of finite energy solutions to general nonlinear Schrödinger systems have exponential decay at infinity. Our results apply positive or sign-changing components, and cooperative, competitive, mixed-interaction systems. As an application, we use derive upper bound for least possible a solution with prescribed number nonradial components.

La percolation bootstrap constitue une classe étendue d’automates cellulaires aux conditions initiales aléatoires. Dans ce travail on développe des outils pour étudier en toute généralité l’une trois classes « d’universalité » de modèles deux dimensions appelée souscritique. On introduit la nouvelle notion densités critiques qui jouent le rôle difficultés les (Bollobás et al.), mais adaptée sou...