Interpretation of the spin glass behaviour of diluted magnetic semiconductors below the nearest-neighbour percolation threshold via realistic Monte Carlo simulations

Karaoulanis, D; Xanthakis, JP; Bacalis, NC

dc.contributor.author	Karaoulanis, D	en
dc.contributor.author	Xanthakis, JP	en
dc.contributor.author	Bacalis, NC	en
dc.date.accessioned	2014-03-01T01:15:40Z
dc.date.available	2014-03-01T01:15:40Z
dc.date.issued	2000	en
dc.identifier.issn	0304-8853	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13656
dc.subject	nearest-neighbour percolation threshold	en
dc.subject	classical Heisenberg Hamiltonian	en
dc.subject	Monte Carlo simulations	en
dc.subject.classification	Materials Science, Multidisciplinary	en
dc.subject.classification	Physics, Condensed Matter	en
dc.subject.other	PHASE	en
dc.title	Interpretation of the spin glass behaviour of diluted magnetic semiconductors below the nearest-neighbour percolation threshold via realistic Monte Carlo simulations	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0304-8853(00)00499-6	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0304-8853(00)00499-6	en
heal.language	English	en
heal.publicationDate	2000	en
heal.abstract	We have performed Monte Carlo simulations of magnetic semiconductors above and below the nearest-neighbour percolation threshold (NNPT) using a classical Heisenberg Hamiltonian with up to third nearest-neighbour (nn) interactions. Large clusters were created allowing use of realistically low magnetic fields (10 G). Above NNPT our results, apart from confirming the existing picture of this class of materials, also show that the inclusion of the second and third (nn) interactions increases the frustration, thus making the transition temperature smaller and closer to experiment than calculated via the first nn interactions only. A physically plausible explanation is given. Below NNPT our results strongly support the validity of the hypothesis (D. Karaoulanis, J.P. Xanthakis, C. Papatriantafillou, J. Magn. Magn. Mater. 161 (1996) 231), that the experimentally observed susceptibility is the sum of two contributions: a paramagnetic one due to isolated magnetic clusters, and a spin-glass contribution due to an 'infinite' percolative cluster formed from exchange interactions of further than first nearest neighbours. Our calculated phase diagram is in very good agreement with the experiment. (C) 2000 Elsevier Science B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS	en
dc.identifier.doi	10.1016/S0304-8853(00)00499-6	en
dc.identifier.isi	ISI:000166237100024	en
dc.identifier.volume	221	en
dc.identifier.issue	3	en
dc.identifier.spage	407	en
dc.identifier.epage	413	en