title: Critical state theory for nonparallel flux line lattices in type-II superconductors.
abstract: Field penetration profiles in type-II superconductors with nonparallel vortex configurations are obtained by a proposed least action principle. We introduce a functional C[H-->] which is minimized for the current density constrained by J-->inDelta(H-->,x-->), where Delta is a bounded set. Within the isotropic case /J-->/< or =J(c)(H), the profiles H-->(x-->,t) are derived for an applied changing excitation. The model can reproduce the physical phenomena of flux transport and consumption, and the magnetization collapse in crossed field measurements.
authors.affiliation: Departamento de Física de la Materia Condensada-I.C.M.A., C.P.S.U.Z., María de Luna 3, E-50.015 Zaragoza, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Badía
authors.forename: C
authors.initials: C
authors.lastname: López