Enhanced Seebeck coefficient by a filling-induced Lifshitz transition in KxRhO2

Article

关键词: THERMOELECTRIC-POWER;    PHASE-TRANSITIONS;    THERMO-EMF;    SUPERCONDUCTIVITY;    CRYSTALS;    NAXCOO2;    METAL;   

DOI  :  10.1103/PhysRevB.99.041112

来源: SCIE

【 摘 要 】

We have systematically measured the transport properties in the layered rhodium oxide KxRhO2 single crystals (0.5 less than or similar to x less than or similar to 0.67), which is isostructural to the thermoelectric oxide NaxCoO2. We find that below x = 0.64 the Seebeck coefficient is anomalously enhanced at low temperatures with increasing x, while it is proportional to the temperature as a conventional metal above x = 0.65, suggesting the existence of a critical content x* similar or equal to 0.65. For the origin of this anomalous behavior, we discuss a filling-induced Lifshitz transition, which is characterized by a sudden topological change in the cylindrical hole Fermi surfaces at the critical content x*.

【 授权许可】

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