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

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 thi n films ranges from 180 to 250 mu Ohm cm as the Tb content varies from 35 t o 46 at. %. Tb-Fe thin films show negative Hall resistivity ranging from -7 .3 to -5.0 mu Ohm cm in the same composition range, giving the normalized r esistivity ratio from -4.1% to -2.0%. On the other hand, the resistivity of Sm-Fe thin films ranges from 150 to 166 mu Ohm 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 mu Ohm 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 conside red to be more suitable for practical applications, since saturation is rea ched at a low magnetic field. (C) 2001 American Institute of Physics.