title: The physical mechanism of magnetic field controlled magnetocaloric effect and magnetoresistance in bulk PrGa compound.
abstract: The PrGa compound shows excellent performance on the magnetocaloric effect (MCE) and magnetoresistance (MR). The physical mechanism of MCE and MR in PrGa compound was investigated and elaborated in detail on the basis of magnetic measurement, heat capacity measurement and neutron powder diffraction (NPD) experiment. New types of magnetic structure and magnetic transition are found. The results of the NPD along with the saturation magnetic moment (MS) and magnetic entropy (SM) indicate that the magnetic moments are randomly distributed within the equivalent conical surface in the ferromagnetic (FM) temperature range. PrGa compound undergoes an FM to FM transition and an FM to paramagnetic (PM) transition as temperature increases. The magnetizing process was discussed in detail and the physical mechanism of the magnetic field controlled magnetocaloric effect (MCE) and the magnetoresistance (MR) was studied. The formation of the plateau on MCE curve was explained and MR was calculated in detail on the basis of the magnetic structure and the analysis of the magnetizing process. The experimental results are in excellent agreement with the calculations. Finally, the expression of MR = β(T)X(2) and its application conditions were discussed, where X is M(H)/Meff, and Meff is the paramagnetic effective moment.
authors.affiliation: State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.|School of Materials Science and Engineering, University of Science &Technology of Beijing, 100083, People's Republic of China.|NIST Center for Neutron Research, National Institute of Standards &Technology, Gaithersburg, MD 20899, USA.
authors.forename: X Q
authors.initials: XQ
authors.lastname: Zheng
authors.affiliation: NIST Center for Neutron Research, National Institute of Standards &Technology, Gaithersburg, MD 20899, USA.|Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742-2115, USA.
authors.forename: H
authors.initials: H
authors.lastname: Wu
authors.affiliation: Beijing Institute of Aerospace Testing Technology, China Aerospace Science &Technology Corporation, Beijing, 100074, People's Republic of China.
authors.forename: J
authors.initials: J
authors.lastname: Chen
authors.affiliation: State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: B
authors.initials: B
authors.lastname: Zhang
authors.affiliation: State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Li
authors.affiliation: State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: F X
authors.initials: FX
authors.lastname: Hu
authors.affiliation: State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: J R
authors.initials: JR
authors.lastname: Sun
authors.affiliation: NIST Center for Neutron Research, National Institute of Standards &Technology, Gaithersburg, MD 20899, USA.
authors.forename: Q Z
authors.initials: QZ
authors.lastname: Huang
authors.affiliation: State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: B G
authors.initials: BG
authors.lastname: Shen