Magnetic and structural properties of MnRh thin Films

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:401

Article

Chaturvedi, Anurag¹  Sepehri-Amin, Hossein²  Ohkubo, Tadakatsu²  Hono, Kazuhiro²  Suzuki, Takao^1,3,4 

[1] Univ Alabama, Ctr Mat Informat Technol, Tuscaloosa, AL 35487 USA

[2] Natl Inst Mat Sci, Elements Strategy Initiat Ctr Magnet Mat, Tsukuba, Ibaraki 3050047, Japan

[3] Univ Alabama, Dept Elect & Comp Engn, Tuscaloosa, AL 35487 USA

[4] Univ Alabama, Dept Met & Mat Engn, Tuscaloosa, AL 35487 USA

关键词: MnRh;    Thin film;    First order transition;    Exchange bias effect;   

DOI  :  10.1016/j.jmmm.2015.10.027

来源: Elsevier

【 摘 要 】

A systematic study of magnetic and structural properties of MnRh thin films fabricated by sputter-deposition onto silica glass has been conducted. The MnRh thin films are found to be of the CsCI-type structure, and ferromagnetic at room temperature. The MnRh thin film undergoes the magnetic phase transition between antiferromagnetic and ferromagnetic states at a temperature around 175 K and 310 K during the cooling and heating process, respectively. The temperature dependence of the magnetization shows a thermal hysteresis of about 120 K. An exchange bias field of about 450 Oe at 5 K was observed with the coercivity of 900 Oe and unidirectional anisotropy constant of about 0.45 erg/cm(2). The magnetic field dependence of M-T shows that the transition temperature of about 230 K remains unchanged with increasing field during the temperature variation process. A detailed STEM-EDS analysis indicates a non-uniform compositional distribution of Mn and Rh with an average composition of Mn58Rh42 at%. A high resolution STEM-HAADF analysis reveals the compositional variations within the CsCI-type MnRh grains. It is proposed that the origin of exchange bias effect is resulted from the exchange coupling between the ferromagnetic region with Mn-rich and the antiferromagnetic region with nearly the equiatomic composition. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

Free