Magnetic and Electrical Properties of Single-Crystalline Mn-Doped Ge Nanowires

Abstract

We report on synthesis of Mn-doped Ge nanowires and their magnetic and electrical properties. The nanowires were grown on the silicon substrate by vapor−liquid−solid mechanism using Au as catalyst and GeCl 4 and MnCl 2 as precursor. Anomalous X-ray scattering measurement makes it clear that Mn atoms are substitutionally incorporated with the diamond network of host Ge sites. Superconducting quantum interference device characterization indicated that the nanowires possess ferromagnetism up to room temperature. X-ray magnetic circular dichroism spectra at Mn L 2,3 -edges showed that doped Mn has local spin moment with the 3d 5 electronic configuration above room temperature, meaning that the ferromagnetism originates from doped Mn 2+ ions. Electrical characterization of a nanowire field effect transistor revealed the improved p-type behavior with hole mobility of 4.95 cm 2 /V·s.