1. Large magnetothermopower effect in Dirac materials (Sr/Ca)MnBi2.
- Author
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Wang, Kefeng, Wang, Limin, and Petrovic, C.
- Subjects
- *
MAGNETORESISTANCE , *DIRAC function , *HEAT treatment of semiconductors , *LINEAR energy transfer ,THERMAL conductivity of metals - Abstract
We report temperature and magnetic field dependence of the thermal transport properties in single crystals of (Sr/Ca)MnBi2 with linear energy dispersion. In SrMnBi2 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 CaMnBi2 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 CaMnBi2 below 50 K. The large magnetothermopower effect in (Sr/Ca)MnBi2 is attributed to the magnetic field shift of chemical potential. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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