Abstract
A quasiperiodic intermediate-valence (IV) system is realized in an icosahedral Au-Al-Yb quasicrystal. X-ray absorption spectroscopy near the Yb L 3 edge indicates that quasiperiodically arranged Yb ions assume a mean valence of 2.61, between a divalent state (4f14, J=0) and a trivalent one (4f13, J=7/2). Magnetization measurements demonstrate that the 4f holes in this quasicrystal have a localized character. The magnetic susceptibility shows a Curie-Weiss behavior above ∼100 K with an effective magnetic moment of 3.81μ B per Yb. Moreover, a crystalline approximant to this quasicrystal is an IV compound. We propose a heterogeneous IV model for the quasicrystal, whereas the crystalline approximant is most likely a homogeneous IV system. At temperatures below ∼10 K, specific heat and magnetization measurements reveal non-Fermi-liquid behavior in both the quasicrystal and its crystalline approximant without either doping, pressure, or field tuning.
Original language | English |
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Article number | 094201 |
Journal | Physical Review B - Condensed Matter and Materials Physics |
Volume | 86 |
Issue number | 9 |
DOIs | |
Publication status | Published - 2012 Sep 10 |
Externally published | Yes |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics