Ytterbium Divalency And Lattice Disorder in Near-Zero Thermal Expansion YbGaGe

Journal Article · Mon Jun 01 00:00:00 EDT 2009 · Phys. Rev. B75:012301,2007

OSTI ID:954011

Booth, C H; Christianson, A D; Lawrence, J M; Pham, L D; Lashley, J C; Drymiotis, F R

While near-zero thermal expansion (NZTE) in YbGaGe is sensitive to stoichiometry and defect concentration, the NZTE mechanism remains elusive. We present x-ray absorption spectra that show unequivocally that Yb is nearly divalent in YbGaGe and the valence does not change with temperature or with nominally 1% B or 5% C impurities, ruling out a valence-fluctuation mechanism. Moreover, substantial changes occur in the local structure around Yb with B and C inclusion. Together with inelastic neutron scattering measurements, these data indicate a strong tendency for the lattice to disorder, providing a possible explanation for NZTE in YbGaGe.

• Research Organization: Stanford Linear Accelerator Center (SLAC)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 954011
• Report Number(s): SLAC-REPRINT-2009-381
• Journal Information: Phys. Rev. B75:012301,2007, Journal Name: Phys. Rev. B75:012301,2007 Vol. 75; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION SPECTRA
CRYSTAL LATTICES
DEFECTS
GALLIUM COMPOUNDS
GERMANIUM COMPOUNDS
IMPURITIES
INELASTIC SCATTERING
INTERMETALLIC COMPOUNDS
NEUTRON DIFFRACTION
ORDER-DISORDER TRANSFORMATIONS
Other
OTHER
STOICHIOMETRY
THERMAL EXPANSION
VALENCE
X-RAY SPECTROSCOPY
YTTERBIUM COMPOUNDS