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

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 نشر من قبل Hiromichi Ohta
 تاريخ النشر 2009
  مجال البحث فيزياء
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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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