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ID 16651
file
creator
Shimizu, Fumihiko
Maniwa, Yutaka
Kume, Kiyoshi
Kawaji, Hitoshi
Ishikawa, Mitsuo
NDC
Physics
abstract
29Si, 23Na, 137Ba, and 135Ba NMR experiments were carried out in the superconducting silicon clathrate compound NaxBaySi46 to study the electronic states above the superconducting transition temperature. We observed three distinct 29Si signals with different Knight shift (2036, 862, and 720 ppm at 90 K with a small temperature dependence of ∼10%), which were ascribed to inequivalent Si sites in the Si46 structure. The results indicate that the conduction-electron spin and/or charge density is strongly site-dependent. At all the atomic sites, the Korringa relation in NMR relaxation was observed, indicative of metallic electronic structure with moderate electronic correlation. The Na and Ba atoms are partially ionized in NaxBaySi46, which shows the noticeable difference from the system of alkali-metal-doped fullerides. The comparison with band calculations is discussed.
journal title
Physical Review B - Condensed Matter and Materials Physics
volume
Volume 54
issue
Issue 18
start page
13242
end page
13246
date of issued
1996-11-01
publisher
American Physical Society
issn
1098-0121
ncid
publisher doi
language
eng
nii type
Journal Article
HU type
Journal Articles
DCMI type
text
format
application/pdf
text version
publisher
rights
Copyright (c) 1996 American Physical Society
relation url
department
Graduate School of Engineering