Large magnetothermopower effect in Dirac materials (Sr/Ca)MnBi2

Abstract

We report temperature and magnetic field dependence of the thermal transport properties in single crystals of (Sr/Ca)MnBi${}_2$ with linear energy dispersion. In SrMnBi${}_2$ thermopower is positive, indicating hole-type carriers and the magnetic field enhances the thermopower significantly. The maximum change of thermopower is about 1600% in 9 T field and at 10 K. A negative thermopower is observed in CaMnBi${}_2$ with dominant electron-type carriers and, in contrast, the magnetic field suppresses the absolute value of thermopower. First-principle band structure shows that the chemical potential is close to the Dirac-cone-like points in linear bands. The magnetic field suppresses the apparent Hall carrier density of CaMnBi${}_2$ below 50 K. The large magnetothermopower effect in (Sr/Ca)MnBi${}_2$ is attributed to the magnetic field shift of chemical potential

3 papges, 3 figures

References in corpus (6)

• The electronic properties of graphene
• Topological Insulators
• Anisotropic Dirac fermions in a Bi square net of SrMnBi2
• Topological Aspect and Quantum Magnetoresistance of $\beta$-Ag${}_2$Te
• Quantum transport of two-dimensional Dirac fermions in SrMnBi2
• Two dimensional Dirac fermions and quantum magnetoresistance in CaMnBi${}_2$

Cited by in corpus (14)

• Topological Semimetals in Square-Net Materials
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• Effect of Eu magnetism on the electronic properties of the candidate Dirac material EuMnBi2
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• Revealing the ultrafast light-to-matter energy conversion before heat diffusion in a layered Dirac semimetal
• Observation of well-defined quasi-particle over a wide energy range in quasi-2D system
• Magnetic structures, spin-flop transition and coupling of Eu and Mn magnetism in the Dirac semimetal EuMnBi${}_2$
• Superconductivity and Dirac Fermions in 112-phase Pnictides
• Interlayer electronic transport in CaMnBi${}_2$ antiferromagnet
• Prediction of the High Thermoelectric Performance of Pnictogen Dichalcogenide Layered Compounds with Quasi-One-Dimensional Gapped Dirac-like Band Dispersion
• Large linear magnetoresistance and magnetothermopower in layered SrZnSb${}_2$
• Twisted nodal wires and three-dimensional quantum spin Hall effect in distorted square-net compounds
• Controlling Magnetic Order, Magnetic Anisotropy, and Band Topology in Semimetals $\mathrm{Sr}(\mathrm{M}{\mathrm{n}}_{0.9}\mathrm{C}{\mathrm{u}}_{0.1})\mathrm{S}{\mathrm{b}}_2$ and $\mathrm{Sr}(\mathrm{M}{\mathrm{n}}_{0.9}\mathrm{Z}{\mathrm{n}}_{0.1})\mathrm{S}{\mathrm{b}}_2$
• Hole Doping and Antiferromagnetic Correlations above the N{é}el temperature of the Topological Semimetal (Sr${}_{1-x}$K${}_x$)MnSb${}_2$