Magnetotransport properties in near-stoichiometric hydride films of YH2+δ under weak fields

Abstract

Articles you may be interested inElectrical and optical characterization of the metal-insulator transition temperature in Cr-doped VO2 thin films Magnetic, magnetotransport, and optical properties of Al-doped Zn 0.95 Co 0.05 O thin films Appl. Phys. Lett. 90, 242508 (2007); 10.1063/1.2748343Electrical properties of nearly stoichiometric GaAs grown by molecular beam epitaxy at low temperatureWe 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 YH 2+␦ . Hall resistance and transverse magnetoresistance measurements were carried out under magnetic fields of up to 1 T at room temperature. The Hall coefficient in YH 2+␦ showed a minimum value of ϳ5 ϫ 10 −12 m 3 / C when the ␦ value reached ϳ−0.1, in accordance with the ␦ dependence of resistivity reported previously. Quantitative analysis based on the present measurements revealed that YH 2+␦ is a compensated metal whose carrier density and mobility were determined to be ϳ1.4ϫ 10 27 ͑ϳ1.9ϫ 10 27 ͒ m −3 and ϳ3.5ϫ 10 −3 ͑ϳ3.1ϫ 10 −3 ͒ m 2 V −1 s −1 , respectively, for ␦ = 0.04 ͑−0.03͒ for both electrons and holes. These carrier parameters were found to account concurrently for the reflection spectral line shapes observed. The compensation observed in YH 2+␦ is at variance with a simple criterion used previously ͓E. Fawcett and W. A. Reed, Phys. Rev. 131, 2463 ͑1963͔͒.

Generation of Spin Current in Bipolar Conductors

“…Recently, a nearly zero Hall coefficient (R H ) achieved without any tuning of physical conditions including magnetic field and temperature has been observed in yttrium dihydride (YH 2 ). 23) The minimum R H value of 5 Â 10 À12 m 3 /C observed so far in YH 2 is fairly small compared with that in other metals, as shown in Table I. 24,25) A singlecarrier regime, wherein R H is given in terms of the carrier density n and the charge q as 1=ðqnÞ, yields a hole density of $1:3 Â 10 30 m À3 for YH 2 .…”

“…Because the single-carrier model has been inferred to be inappropriate for YH 2 , the bipolar model was applied, 23) in accordance with the theoretical prediction about the topology of the Fermi surface. 26) The analytic expression of R H for the bipolar model is given under the weak-field condition (B ( 1) by 27)…”

Advanced Moderator Material Handbook

“…Electrical properties of metal hydrides have been measured using magnetoresistance methods, where the material is subjected to a magnetic field and the potential difference across the sample is correlated to the sample geometry and the electrical resistivity [19].…”

“…charge carrier concentration of yttrium dihydride was measured bySakai, et al as between 1.1 and 1.4 × 1027 m -3[19]. Sakai, et al also measured the electrical resistivity of yttrium dihydride as approximately 8.4 ×10 -12 Ωm.…”

Negative Magnetoresistance Generated by Combination of Spin–Orbit Interaction and Applied Magnetic Field

“…Our methodology and apparatus of magnetotransport measurement are the same as those described in the literature. 17) Figure 3 shows our experimental results on the Hall resistivities in Ni film with a thickness of 100 nm and Gd film with a thickness of 300 nm. The Hall resistivity formula given by eq.…”