Energy gap evolution in the optical spectra of Kondo alloy system Yb1-xLuxB12

Citation
H. Okamura et al., Energy gap evolution in the optical spectra of Kondo alloy system Yb1-xLuxB12, PHYSICA B, 281, 2000, pp. 280-281
Citations number
11
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICA B
ISSN journal
0921-4526 → ACNP
Volume
281
Year of publication
2000
Pages
280 - 281
Database
ISI
SICI code
0921-4526(200006)281:<280:EGEITO>2.0.ZU;2-4
Abstract
We have measured the optical conductivity spectra [sigma(omega)] of Yb1-xLu xB12 (x = 0, 0.25, 0.5, 0,75, 1) single crystals, where the system evolves from a Kondo semiconductor (YbB12, x = 0) to a non-magnetic metal (LuB12, x = 1). For YbB12, sigma(omega) has a clear energy gap at low temperatures, with the onset of sigma(omega) at similar to 20 meV and a 'shoulder' at sim ilar to 40 meV. As x increases, the gap is progressively filled in from the bottom, while the position of the shoulder remains almost the same. This s pectral evolution suggests that a Lu-related band grows within the gap, and that the magnitude of the intrinsic Kondo semiconducting gap is basically unaffected by the Lu substitution. (C) 2000 Elsevier Science B.V. All right s reserved.