Short-range ordering in β-YH2+δ and β-YD2+δ thin films studied by Raman spectroscopy -: art. no. 134102

被引：11

作者：

Carsteanu, AM ^{[1
]}

Rode, M ^{[1
]}

Zur, D ^{[1
]}

Borgschulte, A ^{[1
]}

Schröter, H ^{[1
]}

Schoenes, J ^{[1
]}

机构：

[1] Tech Univ Braunschweig, Inst Halbleiterphys & Opt, D-38106 Braunschweig, Germany

来源：

PHYSICAL REVIEW B | 2004年 / 69卷 / 13期

关键词：

D O I：

10.1103/PhysRevB.69.134102

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The metal-insulator transition of Y films grown on (111) CaF2 substrates and capped with Pd is monitored using Raman spectroscopy. At room temperature the spectra display one Raman active line for cubic YH2.0 and nine Raman active lines for hexagonal YH3. For an intermediate hydrogen concentration in YH2+delta with deltaless than or equal to0.1 a third spectrum is observed, which cannot be explained by a mixture of the border cubic and hexagonal phases. The new spectrum is also observed for an in situ grown YH2+delta film, i.e., a sample which was hydrogenated during the growth process of the film. A factor group analysis indicates that this intermediate phase has the I4/mmm structure. Temperature-dependent measurements for these samples point to a short-range ordering of the hydrogen sublattice above 150 K.

引用

页码：134102 / 1

页数：6

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