Non-saturating linear magnetoresistance in phase separated amorphous Ag10Ge15Te75 films

We report non-saturating linear magnetoresistance (LMR) in silver-poor composite thin films of Ag10Ge15Te75 (AGT). The LMR increases with decreasing temperature and reaches a value of 110% at 200 K under a magnetic field of 70 kOe. The observed magnetoresistance is proportional to carrier mobility due to identical temperature dependencies. The microstructures of AGT films annealed at different temperature are investigated by TEM observations. The observed LMR effect is resulting from the inhomogeneous distribution of conductivity caused by highly conductive Ag2Te and GeTe4 precipitates, which generate a current distortion in the surrounding amorphous silver-poor Ag–Ge–Te matrix.