Origin of the Anomalous Magnetic Behavior in Single Crystal <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>Fe</mi></mrow><mrow><mn>3</mn></mrow></msub></mrow><mrow><msub><mrow><mi>O</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span> Films

D. T. Margulies; F. T. Parker; M. L. Rudee; F. E. Spada; J. N. Chapman; P. R. Aitchison; A. E. Berkowitz

doi:10.1103/PhysRevLett.79.5162

Origin of the Anomalous Magnetic Behavior in Single Crystal ${Fe}_{3} O_{4}$ Films

D. T. Margulies, F. T. Parker, M. L. Rudee, F. E. Spada, J. N. Chapman, P. R. Aitchison, and A. E. Berkowitz

Phys. Rev. Lett. 79, 5162 – Published 22 December 1997

Abstract

Antiphase boundaries (APBs) were observed in ${Fe}_{3} O_{4}$ single crystal films grown on MgO. The APBs are an intrinsic consequence of the nucleation and growth mechanism in films. Across an APB, the intrasublattice superexchange coupling is greatly strengthened, while the intersublattice superexchange coupling is weakened, reversing the dominant interaction from that found in the bulk. Thus the APB separates oppositely magnetized regions, consistent with Lorentz microscopy measurements. The APBs induce very large saturation fields and nearly random magnetization distribution in zero field.

Received 10 June 1997

DOI:https://doi.org/10.1103/PhysRevLett.79.5162

Authors & Affiliations

D. T. Margulies¹, F. T. Parker¹, M. L. Rudee¹, F. E. Spada¹, J. N. Chapman², P. R. Aitchison², and A. E. Berkowitz¹

¹Center for Magnetic Recording Research, University of California at San Diego, La Jolla, California 92093-0401
²Department of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom