中国物理B ›› 2016, Vol. 25 ›› Issue (10): 107503-107503.doi: 10.1088/1674-1056/25/10/107503

• SPECIAL TOPIC—Non-equilibrium phenomena in soft matters • 上一篇    下一篇

Large linear magnetoresistance in a new Dirac material BaMnBi2

Yi-Yan Wang(王义炎), Qiao-He Yu(郁巧鹤), Tian-Long Xia(夏天龙)   

  1. 1 Department of Physics, Renmin University of China, Beijing 100872, China;
    2 Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices, Renmin University of China, Beijing 100872, China
  • 收稿日期:2016-06-23 修回日期:2016-08-04 出版日期:2016-10-05 发布日期:2016-10-05
  • 通讯作者: Tian-Long Xia E-mail:tlxia@ruc.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant No. 11574391), the Fundamental Research Funds for the Central Universities, and the Research Funds of Renmin University of China (Grant No. 14XNLQ07).

Large linear magnetoresistance in a new Dirac material BaMnBi2

Yi-Yan Wang(王义炎)1,2, Qiao-He Yu(郁巧鹤)1,2, Tian-Long Xia(夏天龙)1,2   

  1. 1 Department of Physics, Renmin University of China, Beijing 100872, China;
    2 Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices, Renmin University of China, Beijing 100872, China
  • Received:2016-06-23 Revised:2016-08-04 Online:2016-10-05 Published:2016-10-05
  • Contact: Tian-Long Xia E-mail:tlxia@ruc.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant No. 11574391), the Fundamental Research Funds for the Central Universities, and the Research Funds of Renmin University of China (Grant No. 14XNLQ07).

摘要:

Dirac semimetal is a class of materials that host Dirac fermions as emergent quasi-particles. Dirac cone-type band structure can bring interesting properties such as quantum linear magnetoresistance and large mobility in the materials. In this paper, we report the synthesis of high quality single crystals of BaMnBi2 and investigate the transport properties of the samples. BaMnBi2 is a metal with an antiferromagnetic transition at TN=288 K. The temperature dependence of magnetization displays different behavior from CaMnBi2 and SrMnBi2, which suggests the possible different magnetic structure of BaMnBi2. The Hall data reveals electron-type carriers and a mobility μ(5 K)=1500 cm2/V·s. Angle-dependent magnetoresistance reveals the quasi-two-dimensional (2D) Fermi surface in BaMnBi2. A crossover from semiclassical MR~H2 dependence in low field to MR~H dependence in high field, which is attributed to the quantum limit of Dirac fermions, has been observed in magnetoresistance. Our results indicate the existence of Dirac fermions in BaMnBi2.

关键词: topological material, Dirac semimetal, magnetoresistance

Abstract:

Dirac semimetal is a class of materials that host Dirac fermions as emergent quasi-particles. Dirac cone-type band structure can bring interesting properties such as quantum linear magnetoresistance and large mobility in the materials. In this paper, we report the synthesis of high quality single crystals of BaMnBi2 and investigate the transport properties of the samples. BaMnBi2 is a metal with an antiferromagnetic transition at TN=288 K. The temperature dependence of magnetization displays different behavior from CaMnBi2 and SrMnBi2, which suggests the possible different magnetic structure of BaMnBi2. The Hall data reveals electron-type carriers and a mobility μ(5 K)=1500 cm2/V·s. Angle-dependent magnetoresistance reveals the quasi-two-dimensional (2D) Fermi surface in BaMnBi2. A crossover from semiclassical MR~H2 dependence in low field to MR~H dependence in high field, which is attributed to the quantum limit of Dirac fermions, has been observed in magnetoresistance. Our results indicate the existence of Dirac fermions in BaMnBi2.

Key words: topological material, Dirac semimetal, magnetoresistance

中图分类号:  (Magnetotransport phenomena; materials for magnetotransport)

  • 75.47.-m
73.43.Qt (Magnetoresistance) 75.30.Gw (Magnetic anisotropy)