Centre for Modeling and Simulation
Savitribai Phule Pune University All Models Are False, Some Are Useful

Technical Report CMS-TR-20050221


Title Large Magnetic Moments and Anomalous Exchange Coupling in As-Doped Mn Clusters
Author/s Mukul Kabir
Unit for Nanoscience and Technology, S. N. Bose National Center for Basic Sciences, JD Block, Sector III, Salt Lake City, Kolkata 700 098, India


D. G. Kanhere
Centre for Modeling and Simulation, Savitribai Phule Pune University, Pune 411 007 India


Abhijit Mookerjee
Unit for Nanoscience and Technology, S. N. Bose National Center for Basic Sciences, JD Block, Sector III, Salt Lake City, Kolkata 700 098, India
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 Mn-Mn coupling for Mn2As and Mn4As clusters, resulting in large cluster magnetic moments, 9 and 17  µB, 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 Mn2As and Mn4As 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.
Keywords
Download [288K pdf]
Citing This Document Mukul Kabir, D. G. Kanhere, and Abhijit Mookerjee , Large Magnetic Moments and Anomalous Exchange Coupling in As-Doped Mn Clusters . Technical Report CMS-TR-20050221 of the Centre for Modeling and Simulation, Savitribai Phule Pune University, Pune 411007, India (2005); available at http://cms.unipune.ac.in/reports/.
Notes, Published Reference, Etc. Published as Physical Review B 73, 075210 (2006)
Contact kanhere AT unipune.ac.in
Supplementary Material


About | People | Programmes | ResearchReports
Alumni | Announcements | WebMail | Contact



© 2004-17 Centre for Modeling and Simulation
Valid HTML 4.01!