Spin-glass behavior and anomalous magnetoresistance in ferromagnetic Ge1-xFexTe epilayer.

We report that the Ge1-xFexTe thin film exhibits spin-glass behavior when the Fe concentration increases to 0.08. A large bifurcation between the zero-field cooling and field cooling temperaturedependent magnetization was observed. The hysteresis loops after zero-field cooling and field cooling show an exchange bias effect. A time-dependent thermoremanent magnetization follows power-law decay, which confirms the existence of spin glass. The anomalous magnetotranport properties present a further evidence for spin-glass behavior and give a freezing temperature Tg~5K in the Ge0.92Fe0.08Te thin film. [ABSTRACT FROM AUTHOR]