Magnetization and magneto-transport measurements on CeBi single crystals

TL;DR

This study synthesizes CeBi single crystals and systematically investigates their magnetic and transport properties, revealing a complex phase diagram, large magnetoresistance at low temperatures, and a transition to negative MR with increasing temperature.

Contribution

It provides the first detailed magnetic and transport phase diagram of CeBi, including the identification of a new phase region and analysis of MR behavior over a range of temperatures and magnetic fields.

Findings

Large MR (~3×10^5%) at 2K and 13.95T

Identification of a new magnetic phase region

MR crossover from positive to negative with temperature

Abstract

We report the synthesis of CeBi single crystals out of Bi self flux and a systematic study of the magnetic and transport properties with varying temperature and applied magnetic fields. From these $R(T,H)$ and $M(T,H)$ data we could assemble the field-temperature ($H-T$) phase diagram for CeBi and visualize the three dimensional $M-T-H$ surface. In the phase diagram, we identify regions with well defined magnetization values, and identify a new phase region. The magnetoresistance (MR) in the low temperature regime shows, above $6~$T a power-law, non-saturated behavior with large MR ($\sim 3\times10^5 \%$ at $2~$K and $13.95~$T), along with Shubnikov-de Haas oscillations. With increasing temperatures, MR decreases, and then becomes negative for $T\gtrsim 10~$K. This crossover in MR seems to be unrelated to any specific magnetic or metamagnetic transitions, but rather is associated with changing from a low-temperature normal metal regime with little or no scattering from the Ce$^{3+}$ moments and an anomalously large MR, to an increased scattering from local Ce moments and a negative MR as temperature increases.