Magneto-Transport Properties in Near -Stoichiometric Hydride  Films of YH2+δ under Weak Fields"

M.Sakai, T.Nanbo, O.Nakamura, Y.Uwatoko,   H.Tajima

We have investigated the basic characteristics of mobile carriers in as-deposited thin films of hexagonal-close-packed Y and hydrogenated films of face-centered-cubic YH2+δ. Hall resistance and transverse magnetoresistance measurements were carried out under magnetic fields of up to 1 T at room temperature. The Hall coefficient in YH2+δ showed a minimum value of ∼5×10−12 m3/C when the δ value reached ∼−0.1, in accordance with the δ dependence of resistivity reported previously. Quantitative analysis based on the present measurements revealed that YH2+δ is a compensated metal whose carrier density and mobility were determined to be ∼1.4×1027 (∼1.9×1027) m−3 and ∼3.5×10−3 (∼3.1×10−3) m2 V−1 s−1, respectively, for δ=0.04(−0.03) for both electrons and holes. These carrier parameters were found to account concurrently for the reflection spectral line shapes observed. The compensation observed in YH2+δ is at variance with a simple criterion used previously [E. Fawcett and W. A. Reed, Phys. Rev.131, 2463 (1963)].

Magneto-Transport Properties in Near -Stoichiometric Hydride  Films of YH2+δ under Weak Fields

Journal of Applied Physics

101

103713