Magnetoelastic effects in SrTi1−xMxO3 (M = Fe, Co, or Cr) epitaxial thin films

Abstract

SrTi[subscript 1−x]M[subscript x]O[subscript 3] films in which M = Fe, Co, or Cr and x=0.04–0.5 have been grown epitaxially on CeO[subscript 2]-buffered Si, SrTiO[subscript 3], and LaAlO3 substrates. Films grown in vacuum containing Fe or Co typically showed a strong uniaxial magnetic anisotropy in the out-of-plane direction, a saturation moment on the order of 0.5μ[subscript B]/Fe or Co, and a magnetization that persists to temperatures of order 1000 K. In contrast, films containing Cr showed no evidence of a spontaneous magnetic moment. The films are typically in a high in-plane compressive strain state due to epitaxial growth. The results are discussed in terms of the magnetoelastic effects from specific ionic valence states, and the magnetization versus temperature curves are fitted to a model for magnetoelastic spin ordering.