Intrinsic ferromagnetism and anomalous Hall effect in GaN thin film by Mn delta doping

作者：Wadekar, Paritosh Vilas; Lin, Yuan-Ting; Lin, Che-Min; Chang, Ching-Wen; Chen, Quark Yung-Sung; Leung, Tsan-Chuen; Cheng, Cheng-Maw; Tu, Li-Wei

来源：Journal of Alloys and Compounds, 2020, 834: 154892.

DOI：10.1016/j.jallcom.2020.154892

• Anomalous Hall effect
• Delta doping
• (Ga,Mn)N

Compound semiconductors doped with magnetically active transition metals (TM) are actively pursued for semiconductor spintronics. Herein we report that delta doping (delta-doping) has been used to incorporate manganese (Mn) into the gallium nitride (GaN) matrix resulting in phase pure highly crystalline heteroepitaxial thin films of (Ga,Mn)N on c-plane sapphire (Al2O3) by plasma-assisted molecular beam epitaxy. Magnetotransport measurements reveal the anomalous Hall effect (AHE) while magnetic measurements show the existence of ferromagnetic ordering. Density functional theory calculations show that d-doping of Mn atom enables exchange interactions between the Mn 3d states and N 2p states thereby resulting in spin polarized holes in the valence band giving rise to observed AHE and ferromagnetism. This work opens new avenues for incorporating spin polarized carriers in III-nitrides based semiconductors by creating magnetically active Mn layers in heterostructures for spintronics applications.

• 单位
  中山大学