Diffusion of Interstitial Mn in the Dilute Magnetic Semiconductor (Ga,Mn)As: The Effect of a Charge State
2008 (English)In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 101, no 17, 177204- p.Article in journal (Refereed) Published
Migration barriers for diffusion of interstitial Mn in the dilute magnetic semiconductor (Ga,Mn)As are studied using first-principles calculations. The diffusion pathway goes through two types of interstitial sites: As coordinated and Ga coordinated. The energy profile along the path is found to depend on the ratio of concentrations between substitutional and interstitial Mn in GaAs. Two regions of distinctly different behavior, corresponding to n-type and p-type (Ga,Mn)As, are identified. The difference in mobility is a reflection of the change in the charge state of Mn interstitials (double donors) that occurs in the presence of substitutional Mn impurities (acceptors). In addition, substitutional Mn impurities are shown to act as traps for interstitial Mn. The effective migration barrier for the positively doubly charged Mn interstitials in p-type (Ga,Mn)As is estimated to vary from 0.55 to about 0.95 eV.
Place, publisher, year, edition, pages
2008. Vol. 101, no 17, 177204- p.
DILUTE MAGNETIC SEMICONDUCTOR, ELECTRONIC STRUCTURE, DEFECTS, DIFFUSION
Condensed Matter Physics Other Electrical Engineering, Electronic Engineering, Information Engineering Physical Chemistry
IdentifiersURN: urn:nbn:se:kth:diva-7895DOI: 10.1103/PhysRevLett.101.177204ISI: 000260383600060ScopusID: 2-s2.0-55049107277OAI: oai:DiVA.org:kth-7895DiVA: diva2:13059
QC 201006242008-01-152008-01-152016-05-09Bibliographically approved