Magnetoresistance in n- and p-type Ag2Te: Mechanisms and applications

Abstract

We compare the large magnetoresistive response of slightly nonstoichiometric ${\mathrm{Ag}}_{\text{2±δ}}\mathrm{Te}$ for a wide range of hole ${\text{(p⩽8×10}}^{17} {\mathrm{cm}}^{\mathrm{-3}})$ and electron ${\text{(n⩽4×10}}^{18} {\mathrm{cm}}^{\mathrm{-3}})$ carrier densities. In the p-type material alone, a characteristic peak in the resistivity $\mathrm{\rho (T,H)}$ is dramatically enhanced and moves to higher temperature with increasing magnetic field, resulting in a high field $\text{(H∼5\hspace{0.05em}}\mathrm{T})$ magnetoresistance that is sizeable even at room temperature. By contrast, n-type specimens are geared for low-field $\text{(H<0.1\hspace{0.05em}}\mathrm{T})$ applications because of a striking linear field dependence of the magnetoresistance that appears to be restricted to the Ag-rich materials.