Structural stability and electronic properties of Er nanowire on Si(001)

The silicon surfaces covered with rare earth metals have attracted great interest in recent years due to the promising device applications. Here we report a systematic study on the structural stability and electronic properties of the Er nanowire on Si(001) surface by ab initio calculations. It is shown that Er atomic chains with a double-core odd-membered-ring (5-7-5) structure on Si(001) surface is one of the most stable structures at lower coverage. Total energy calculations show that Er atoms prefer ferromagnetic coupling with a spin moment of 2.04-2.06 ?B on Er sites derived from the 4f electrons. Electronic band structure and band-decomposed charge density distribution calculations show that the odd-membered-ring (5-7-5) structure has a semiconducting feature with a small indirect band gap of 0.13 eV. This study provides a new insight for further exploration of self-assembled nanowires of rare-earth metal on silicon surfaces.

Automated summary

In recent years, silicon surfaces covered with rare earth metals have attracted great interest due to their promising device applications. Here, we report a systematic study on the structural stability and electronic properties of Er nanowires on the Si(001) surface using ab initio calculations. Our results show that Er atomic chains with a double-core odd-membered-ring (5-7-5) structure on the Si(001) surface are among the most stable structures at lower coverage. Total energy calculations reveal that Er atoms prefer ferromagnetic coupling with a spin moment of 2.04-2.06 ?B on Er sites derived from the 4f electrons. Electronic band structure calculations demonstrate that the odd-membered-ring (5-7-5) structure exhibits a semiconductor feature with a small indirect band gap of 0.13 eV. This study provides new insights for further exploration of self-assembled nanowires of rare-earth metals on silicon surfaces.