mu SR studies of grey and white tin, alpha- and beta-Sn
2009 (English)In: Physica. B, Condensed matter, ISSN 0921-4526, Vol. 404, no 5-7, 884-887 p.Article in journal (Refereed) Published
The behaviour of monatomic hydrogen defect centres is modelled using implanted positive muons in both allotropes of elemental tin. A new search for paramagnetic muonium is made in alpha-Sn, the semiconducting allotrope with the diamond structure. No deep state is found, nor any enhanced Korringa relaxation that would suggest localized moment formation on interstitial protons in this intriguing material. In relation to muonium in the other Group-IV semiconductors, tantalizing indications of shallow state formation below 30 K suggest that a deep-to-shallow transition may be responsible. The diamagnetic state remains static to 200 K and may be tentatively identified as the bond-centred positive ion, by comparison with recent data for silicon. This behaviour contrasts with the abrupt onset of mobility at 50K for muons in beta-Sn, the normal metallic allotrope with tetragonal structure, for which a more conventional interstitial site has lately been determined. Mobility studies are admittedly difficult in the presence of such weak nuclear magnetism but a discrepancy arises between reported migration barriers in white tin.
Place, publisher, year, edition, pages
2009. Vol. 404, no 5-7, 884-887 p.
Muon diffusion, Hydrogen defect centres, alpha-Sn, beta-Sn
IdentifiersURN: urn:nbn:se:uu:diva-148882DOI: 10.1016/j.physb.2008.11.145ISI: 000265469800086OAI: oai:DiVA.org:uu-148882DiVA: diva2:403459