Inhomogeneous magnetostriction states in uniaxial ferromagnetic films

Surface magnetoelastic Love waves and nonuniform distributions of the magne tization and elastic strains are investigated in a uniaxial ferromagnetic f ilm on a massive nonmagnetic substrate in a tangential external magnetic fi eld. A new inhomogeneous phase is predicted having spatial modulation of th e order parameter, arising from magnetostrictive coupling of the magnetizat ion with lattice strains near the interface of the magnetoelastic and elast ic media. It is shown that, at some critical magnetic field H-c, different from the orientational transition field in an isolated sample, a magnetoela stic Love wave propagating parallel to the magnetization vector in the film plane becomes unstable. The frequency and group velocity of the wave vanis h at wave number k=k(c)not equal 0 and the wave freezes, forming a domain s tructure localized in the film and adjoining substrate. (C) 1999 American I nstitute of Physics. [S1063-7834(99)02204-2].