Spontaneous Hall effect in amorphous Tb–Fe and Sm–Fe thin films

Abstract

The spontaneous Hall effect in amorphous Tb–Fe and Sm–Fe thin films, which possess excellent magnetic softness, is investigated to seek a possibility of practical applications of these thin films. The resistivity of Tb–Fe thin films ranges from 180 to 250 μΩ cm as the Tb content varies from 35 to 46 at. %. Tb–Fe thin films show negative Hall resistivity ranging from −7.3 to −5.0 μΩ cm in the same composition range, giving the normalized resistivity ratio from −4.1% to −2.0%. On the other hand, the resistivity of Sm–Fe thin films ranges from 150 to 166 μΩ cm as the Sm content varies from 22 to 31 at. %. Sm–Fe thin films show positive Hall resistivity which varies from 7.1 to 2.8 μΩ cm in the same composition range, giving the normalized resistivity ratio from 4.8% to 1.7%. Between the two different sets of samples, Tb–Fe thin films with perpendicular anisotropy are considered to be more suitable for practical applications, since saturation is reached at a low magnetic field.