Abstract
We report electronic and magnetic properties of pure and arsenic-doped manganese clusters from density functional theory using spin-polarized generalized gradient approximation for the exchange-correlation energy. We see for both the cases, noncollinear treatment of spins are indeed necessary. The arsenic atom stabilizes manganese clusters, which is further accompanied by the ferromagnetic coupling for and clusters, resulting in large cluster magnetic moments, 9 and , respectively. We show in doped clusters, exchange coupling are anomalous and behave quite differently from the Ruderman-Kittel-Kasuya-Yosida-type predictions. Finally, it is suggested that, if grown in the low temperature MBE, the giant magnetic moments due to ferromagnetic Mn ordering and their large enough exchange coupling parameter in and could play an important role on the ferromagnetism and on the observed large variation in the Curie temperature of the Mn-doped III-V semiconductors.
- Received 21 February 2005
DOI:https://doi.org/10.1103/PhysRevB.73.075210
©2006 American Physical Society