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Cellular automaton study of timedynamics of avalanche breakdown in IMPATT diodes
(1998)Employing a recently developed efficient cellular automaton technique for solving Boltzmann's transport equation for realistic devices, we present a detailed study of the carrier dynamics in GaAs avalanche pin (IMPATT) ... 
An efficient multigrid poisson solver for device simulations
(1996)The aim of this paper is to show that the multigrid approach can provide an efficient twodimensional Poisson solver used in the analysis of realistic semiconductor devices based on particle simulators. Our robust implementation ... 
General properties of the decay amplitudes for massless particles
(ELSEVIER SCIENCE BV, 1996)We derive the kinematical constraints which characterize the decay of any massless particle in flat spacetime. We show that in perturbation theory the decay probabilities of photons and YangMills bosons vanish to all ... 
Effect of a scaledependent cosmological term on the motion of small test particles in a Schwarzschild background
(ELSEVIER SCIENCE BV, 1999)It was recently suggested that the gravitational action could contain a scaledependent cosmological term, depending on the length or momentum scale characteristic of the processes under consideration. In this work we ... 
Homoclinic solutions of quasiperiodic Lagrangian systems
(Khayyam Publishing, 1995)We consider quasiperiodic positive definite Lagrangian systems and establish the existence of one or more solutions homoclinic (namely asymptotic as $t o \pm \infty$) to a quasiperiodic solution. These results are obtained ... 
Remarks on the algorithm of Sakawa for optimal control problems
(1998)A general optimal control problem for ordinary differential equations is considered. For this problem, some improvements of the algorithm of Sakawa are discussed. We avoid any convexity assumption and show with an example ... 
Forced oscillations for singular dynamical systems with an application to the restricted three body problem
(Elsevier, 1991)We consider forced dynamical systems with two degrees of freedom having singular potentials and we prove existence of infinitely many classical (noncollision) periodic solutions. These solutions have a prescribed rotation ... 
Doubly asymptotic trajectories of Lagrangian systems in homogeneous force fields
(Springer Verlag (Germany), 1998)We study Lagrangian systems with symmetry under the action of a constant generalized force in the direction of the symmetry field. After Routh's reduction, such systems become nonautonomous with Lagrangian quadratic in ...