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arXiv · 0910.3753

Electric-Field Modulation of Thermopower for the KTaO3 Field Effect Transistors

Akira Yoshikawa·Kosuke Uchida·Kunihito Koumoto·Takeharu Kato·Yuichi Ikuhara·Hiromichi Ohta
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Abstract

We show herein fabrication and field-modulated thermopower for KTaO3 single-crystal based field-effect transistors (FETs). The KTaO3 FET exhibits field effect mobility of ~8 cm2/Vs, which is ~4 times larger than that of SrTiO3 FETs. The thermopower of the KTaO3 FET decreased from 600 to 220 microV/K by the application of gate electric field up to 1.5 MV/cm, ~400 microV/K below that of an SrTiO3 FET, clearly reflecting the smaller carrier effective mass of KTaO3.

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Akira Yoshikawa, Kosuke Uchida, Kunihito Koumoto, Takeharu Kato, Yuichi Ikuhara, Hiromichi Ohta. 2009-11-19. Electric-Field Modulation of Thermopower for the KTaO3 Field Effect Transistors. https://doi.org/10.1143/apex.2.121103

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