Thermoelectric Power Observation of Nearly-Commensurate Charge-Density Wave Phase in 1T-TaS₂

Abstract

The temperature dependence of Seebeck coefficient of 1T-TaS₂ is observed in the nearly-commensurate charge-density wave phase with simultaneous measurement of resistivity. Seebeck coefficient is mainly negative and shows complicated behaviors with large hysteresis. At about 280 K in the heating process, we found distinctive anomalies both in Seebeck coefficient and in resistivity, which may correspond to the new phase transition found in the thermal expansion measurement recently. The possible electronic structures in the nearly-commensurate phase are discussed on the basis of the Seebeck effect observations.