2018/07/31 by G. He, Gengming He, R. Belanger +3 · 2 citations
Materials Science · Physics and Astronomy · #Condensed matter physics #Dipole #Ferromagnetism #Magnetic Properties and Applications #Magnetic field #Magnetic properties of thin films #Magnetism #Magnetization #Phase (matter) #Phase transition #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Spin (aerodynamics) #Thermodynamics #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.98.155429
published in Physical review. B./Physical review. B 98(15) (American Physical Society) · 11 pages, 4 figures
openalex publication_date 2018/10/19 · arxiv created 2018/11/22 · arxiv updated 2018/11/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The influence of long-range dipole interactions on two-dimensional magnetism has been studied extensively in the spin-reorientation transition of ferromagnetic ultrathin films. Although there is a great deal of experimental information on the perpendicular domain phase that is stabilized by dipole interactions, the transitions to or from the domain phase are subtle and difficult to characterize experimentally. Magnetic susceptibility measurements show no divergence in the vicinity of the spin-reorientation transition as a function of thickness---a null result that is difficult to interpret with confidence. This paper reports separate dynamical and equilibrium versions of the reorientation transition in Fe/2ML Ni/W(110) films, using measurements of the magnetic susceptibility as the films are grown. The dynamical version occurs when increasing the film thickness causes the domain walls to depin, and the system moves from a configuration that minimizes local energetics to one that minimizes global energetics. The dynamical transition is marked by a divergent magnetic susceptibility measured with a field applied along the in-plane W[001] direction. A comparative study of the two versions of the same spin-reorientation transition aids in the experimental characterization of the effects of dipole interactions on the phase transitions. This comparison confirms the original null result found in magnetic susceptibility measurements of the equilibrium transition; despite its name, the spin-reorientation transition in ferromagnetic ultrathin films has no critical phase transition in either the magnetization or its orientation.