title: Semianalytic solution of the Kramers exit problem for a small ferromagnetic particle.
abstract: The distribution Q(t) of magnetization reversal times in a small uniaxial particle is computed here directly from Brown's Fokker-Planck equation. Constant applied field and axial symmetry are assumed. The Laplace transform of Q(t) has the form Q(z)=F(1)(z)/F(2)(z) where the regular functions F(i)(z) are defined by a solution of a Volterra integral equation. A separate integral equation is derived for the function dF(2)(z)/dz, and the poles and residues of Q(z) may then be found numerically with arbitary precision.
authors.affiliation: Institute of Physics, Academia Sinica, Taipei 115, Taiwan.
authors.forename: I
authors.initials: I
authors.lastname: Klik
authors.forename: Y D
authors.initials: YD
authors.lastname: Yao