Observation of electric and magnetic properties in a diluted magnetic semiconductor GaMnAs/GaAs (111)

We report on the ferroelectric and ferromagnetic behaviors of a Mn doped GaAs epilayer grown on a GaAs (111) substrate by molecular beam epitaxy. We investigated the structural, electrical, and ferromagnetic properties of the Mn doped GaAs epilayer by high resolution x-ray diffraction, anomalous Hall effect, and superconducting quantum interference device measurements. We obtained the ferromagnetic and ferroelectric Curie temperature to be 50 K and 350 K, respectively, which were confirmed by the anomalous Hall effect, temperature dependence of magnetization, and tan δ vs. temperature. Furthermore, we demonstrated ferroelectric switching behaviors of the Mn doped GaAs epilayer by electric force microscopy.

► Ferroelectric characteristic in GaMnAs.
► Switching behaviors are realized according to various electric fields.
► tan δ indicates that ferroelectric Curie temperature is 350 K.
► This means that GaMnAs has multiferroic properties.