APS Logo

Ferroelectric field effect modulation of Superconductivity in LaAlO<sub>3</sub>/KTaO<sub>3</sub> Heterointerface

ORAL

Abstract

We report the ferroelectric field effect control of superconductivity in the two-dimensional electron gas (2DEG) at LaAlO3 (LAO)/KTaO3 (KTO) interface. We deposit 7-8 nm amorphous LAO layer on the (111) KTO substrates using RF magnetron sputtering system. The sample becomes superconducting below 1.7 K. We obtain free-standing ferroelectric PbZr0.2Ti0.8O3 (PZT) membrane by epitaxial growth of single crystalline PZT films on Sr3Al2O6 (SAO) buffered (001) STO substrates and dissolving SAO in water. We then fabricate LAO/KTO into four-point devices with the PZT membranes transferred on top, forming ferroelectric field effect transistors. Switching the polarization of PZT leads to nonvolatile modulation of the channel conductance by over two orders of magnitude at 300 K. In the as-prepared state, the system becomes more conductive with higher critical temperature compared with the standalone sample and shows weak antilocalization behavior in the metallic sample. Switching PZT to the polarization up state leads to an insulating behavior over the entire temperature range investigated. We discuss the effects of carrier density and spin-orbit coupling on the transport properties of the 2DEG.

–

Presenters

  • Yifei Hao

    University of Nebraska - Lincoln, Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience,University of Nebraska - Lincoln, Physics and Astronomy, University of Nebraska-Lincoln

Authors

  • Yifei Hao

    University of Nebraska - Lincoln, Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience,University of Nebraska - Lincoln, Physics and Astronomy, University of Nebraska-Lincoln

  • Qiuchen Wu

    University of Nebraska - Lincoln, Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Department of Physics and Astronomy & Nebraska Center for Materials and NanoscienceUniversity of Nebraska - Lincoln, Physics and Astronomy, University of Nebraska-Lincoln

  • Kun Wang

    University of Nebraska - Lincoln, Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Department of Physics and Astronomy & Nebraska Center for Materials and NanoscienceUniversity of Nebraska - Lincoln, Physics and Astronomy, University of Nebraska-Lincoln

  • Jia Wang

    Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, University of Nebraska-Lincoln, Department of Physics and Astronomy & Nebraska Center for Materials and NanoscienceUniversity of Nebraska-Lincoln, Physics and Astronomy, University of Nebraska-Lincoln

  • Xinyi Du

    Washington University, St. Louis

  • Erik Henriksen

    Washington University in Saint Louis, Washington University, St. Louis, Department of Physics, Washington University in St. Louis, MO 63130

  • Xia Hong

    Physics and Astronomy, University of Nebraska-Lincoln, Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln