Anomalous Hall effect in CoxSi1−x granular films deposited by magnetron co-sputtering

Abstract

In this research, CoxSi1−x granular films with Co volume fraction (x) varying from 0.36 to 1 were prepared by using a magnetron co-sputtering method. The influence of x on the temperature-dependent longitudinal resistivity ($${\rho _{xx}}$$) and anomalous Hall effect (AHE) in CoxSi1−x granular films were systematically studied. The dependence of $${\rho _{xx}}$$ on measuring temperature could be explained by the superposition of fluctuation-induced tunneling (FIT) process and temperature-dependent scattering. Interestingly, the contribution from scattering and FIT can be distinguished. The saturated Hall resistivity ($$\rho _{{xy}}^{A}$$) increased monotonically with decreasing x. In addition, the $$\rho _{{xy}}^{A}$$ amplified nearly 26-fold as x decreased from 1 to 0.4. For the pure Co film (x = 1), the intrinsic and side jump mechanisms dominated the Hall transport. However, the deviation of classical scaling relation was observed in other samples, which was mainly ascribed to the influence of interfacial scattering.