Large unsaturated magnetoresistance and electronic structure studies of single-crystal GdBi

Abstract

Single crystal of the binary equiatomic compound GdBi crystallizing in the rock-salt-type cubic crystal structure with the space group $Fm\overline{3}m$ has been grown by flux method. The electrical and magnetic measurements have been performed on well-oriented single crystals. The antiferromagnetic ordering of the Gd moments is confirmed at ${T}_{\mathrm{N}}=27.5$ K. The magnetization measurement performed at 2 K along the principal crystallographic direction [100] attained a value of $1.3\phantom{\rule{0.16em}{0ex}}{\textmu{}}_{B}$/Gd in a field of 7 T, which is about 5 times smaller than its saturation value of $7\phantom{\rule{0.16em}{0ex}}{\textmu{}}_{B}$. Zero-field electrical resistivity reveals a sudden drop at 27.5 K, suggesting a reduction in the spin disorder scattering due to the antiferromagnetic alignment of the Gd moments. The residual resistivity at 2 K is 390 $\mathrm{n}\mathrm{\ensuremath{\Omega}}\mathrm{cm}$, suggesting a good quality of the grown crystal. The magnetoresistance attains a value of ${10}^{4}%$ with no signature of saturation, in a field of 14 T at $T=2$ K. Shubnikov--de Hass oscillations have been observed in the high field range of the magnetoresistance with three fundamental frequencies corresponding to the extremal areas of the Fermi surface. Our results suggest that the extremely large unsaturated magnetoresistance in this compound is due to near compensation of the charge carriers. We also performed angle-resolved photoelectron spectroscopy measurements with different photon energies and compared our results with the calculated band structure of GdBi.