Hall Effect and Magnetoresistance in Gd_xY_1−xH₂(x\( \fallingdotseq \) 0.4)

Abstract

We are aiming at the construction of the bipolar conducting system, the holes and electrons of which are spin-polarized such that the spin current is generated through either the ordinary or anomalous Hall effects. Taking advantage of the quasi-zero Hall coefficient characteristic (QZHC) of YH 2 in which electrons and holes have approximately the same carrier density and mobility, Gd was incorporated to form a magnetic QZHC system Gd x Y 1-x H 2 (x=0.39). The zero field specific resistivity (ρ 0), Hall resistivity (HR), and transverse magnetoresistivity (TMR) in Gd x Y 1-x H 2 (x=0.39) were measured as a function of temperature ranging from 4 to 400 K. Huge signals were observed in both HR and TMR around 210 K, well synchronized with the abrupt change observed in ρ 0. Two type of interpretation, i.e., the ordinary Hall and anomalous Hall effect models are given to discuss the feasibility of each mechanism based on our experimental results.