Theory of the dipole-exchange spin wave spectrum in ferromagnetic films with in-plane magnetization revisited

We present a refinement of the widely accepted spin-wave spectrum that Kalinikos and Slavin computed for magnetic films with an in-plane magnetization (1986). The spin wave follows from diagonal approximation in this theory becomes inaccurate relatively thick films, as has already been noted by Kreisel et al. (2009). Rather than solving integrodifferential equation which magnetostatic Green's function, done Slavin, we impose exchange boundary conditions on bulk solutions. This problem accurate analytical solution is quantitatively different commonly used films.