Anomalous magnetotransport in (Y${}_{1-x}$Gd${}_x$)Co${}_2$ alloys: interplay of disorder and itinerant metamagnetism

Abstract

New mechanism of magnetoresistivity in itinerant metamagnets with a structural disorder is introduced basing on analysis of experimental results on magnetoresistivity, susceptibility, and magnetization of structurally disordered alloys (Y${}_{1-x}$Gd${}_x$)Co${}_2$. In this series, YCo${}_2$ is an enhanced Pauli paramagnet, whereas GdCo${}_2$ is a ferrimagnet (T${}_{\mathrm{c}}$=400 K) with Gd sublattice coupled antiferromagnetically to the itinerant Co-3d electrons. The alloys are paramagnetic for $x<0.12$. Large positive magnetoresistivity has been observed in the alloys with magnetic ground state at temperatures T$<$T${}_{\mathrm{c}}$. We show that this unusual feature is linked to a combination of structural disorder and metamagnetic instability of itinerant Co-3d electrons. This new mechanism of the magnetoresistivity is common for a broad class of materials featuring a static magnetic disorder and itinerant metamagnetism.

7 pages 7 figures

References in corpus (2)

• Interplay of disorder and spin fluctuations in the resistivity near a quantum critical point
• On the residual resistivity near a two dimensional metamagnetic quantum critical point

Cited by in corpus (3)

• Normal and inverse magnetocaloric effects in structurally disordered Laves phase Y${}_{1-x}$Gd${}_x$Co${}_2$ (0 $\le$ x $\le$ 1) compounds
• Effect of static and dynamic disorder on electronic transport of $RC{o}_2$ compounds: a study of $Ho(A{l}_{x}C{o}_{1-x}{)}_2$ alloys
• Role of domain wall fluctuations in non-Fermi liquid behavior of metamagnets