Two-Carrier Transport Induced Hall Anomaly and Large Tunable Magnetoresistance in Dirac Semimetal Cd3As2 Nanoplates

• Published in: ACS nano Vol. 10; no. 6; pp. 6020 - 6028
• Main Authors: Li, Cai-Zhen, Li, Jin-Guang, Wang, Li-Xian, Zhang, Liang, Zhang, Jing-Min, Yu, Dapeng, Liao, Zhi-Min
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 28.06.2016
• Subjects: magnetoresistance; Dirac semimetal; temperature dependence; two-band transport; Hall resistance
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/acsnano.6b01568

Cd3As2 is a model material of Dirac semimetal with a linear dispersion relation along all three directions in the momentum space. The unique band structure of Cd3As2 is made with both Dirac and topological properties. It can be driven into a Weyl semimetal by symmetry breaking or a topological insulator by enhancing the spin–orbit coupling. Here we report the temperature and gate voltage-dependent magnetotransport properties of Cd3As2 nanoplates with Fermi level near the Dirac point. The Hall anomaly demonstrates the two-carrier transport accompanied by a transition from n-type to p-type conduction with decreasing temperature. The carrier-type transition is explained by considering the temperature-dependent spin–orbit coupling. The magnetoresistance exhibits a large nonsaturating value up to 2000% at high temperatures, which is ascribed to the electron–hole compensation in the system. Our results are valuable for understanding the experimental observations related to the two-carrier transport in Dirac/Weyl semimetals, such as Na3Bi, ZrTe5, TaAs, NbAs, and HfTe5.