Magnetism of epitaxial Tb films on W(110) studied by spin-polarized low-energy electron microscopy

TL;DR

This study investigates the magnetic properties of epitaxial terbium (Tb) films on tungsten (W(110)) using spin-polarized low-energy electron microscopy, revealing in-plane magnetization and temperature-dependent magnetic contrast.

Contribution

It provides the first in-situ analysis of magnetic contrast and electron reflectivity in epitaxial Tb films on W(110), including temperature dependence and critical behavior.

Findings

Magnetic contrast observed in annealed films

Maximum spin asymmetry of about 1% in electron reflectivity

Magnetization is in-plane and decreases with temperature following a power law

Abstract

Thin epitaxial films of Tb metal were grown on a clean W(110) substrate in ultra-high vacuum and studied in-situ by low-energy electron microscopy. Annealed films present magnetic contrast in spin-polarized low-energy electron microscopy. The energy dependence of the electron reflectivity was determined and a maximum value of its spin asymmetry of about 1\% was measured. The magnetization direction of the Tb films is in-plane. Upon raising the temperature, no change in the domain distribution is observed, while the asymmetry in the electron reflectivity decreases when approaching the critical temperature, following a power law $ \sim (1 - T/T_C)^\beta$ with a critical exponent $\beta$ of 0.39.