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arXiv · 2209.01089

Multiband effects in thermoelectric and electrical transport properties of kagome superconductors $A$V$_3$Sb$_5$ ($A$ = K, Rb, Cs)

Xinrun Mi·Wei Xia·Long Zhang·Yuhan Gan·Kunya Yang·Aifeng Wang·Yisheng Chai·Yanfeng Guo·Xiaoyuan Zhou·Mingquan He
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Abstract

We studied the effects of multiband electronic structure on the thermoelectric and electrical transport properties in the normal state of kagome superconductors $A$V$_3$Sb$_5$ ($A$ = K, Rb, Cs). In all three members, the multiband nature is manifested by sign changes in the temperature dependence of the Seebeck and Hall resistivity, together with sublinear response of the isothermal Nernst and Hall effects to external magnetic fields in the charge ordered state. Moreover, ambipolar transport effects appear ubiquitously in all three systems, giving rise to sizable Nernst signal. Finally, possible origins of the sign reversal in the temperature dependence of the Hall effect are discussed.

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Xinrun Mi, Wei Xia, Long Zhang, Yuhan Gan, Kunya Yang, Aifeng Wang, Yisheng Chai, Yanfeng Guo, Xiaoyuan Zhou, Mingquan He. 2022-09-02. Multiband effects in thermoelectric and electrical transport properties of kagome superconductors $A$V$_3$Sb$_5$ ($A$ = K, Rb, Cs). https://doi.org/10.1088/1367-2630/ac8e24

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