Photo-induced stabilization and enhancement of the ferroelectric polarization in Ba$_{0.1}$Sr$_{0.9}$TiO$_{3}$/La$_{0.7}$Ca(Sr)$_{0.3}$MnO$_{3}$ thin film heterostructures

ORAL

Abstract

We demonstrate that optically pumping carriers across the interface between ferroelectric Ba$_{0.1}$Sr$_{0.9}$TiO$_{3}$ and ferromagnetic La$_{0.7}$Ca(Sr)$_{0.3}$MnO$_{3}$ thin films can not only stabilize but also enhance (``write'') the remanent polarization, which breaks crystal inversion symmetry, generating an optical second-harmonic signal that we ``read.'' The new photo-induced (``written'') ferroelectric state remains stable at low temperatures for over one day after removing the laser pulse. By optically decoupling the energy of the internal electric field from the ferroelectric double potential wells, we show that the displacement of the Ti atom increases, leading to a larger, more stable polarization state that may be suitable for applications in data storage (using similar writing and reading processes) as well as energy storage (e.g., solar nanocapacitors).

*This work was performed at the Center for Integrated Nanotechnologies, a U.S. Department of Energy, Office of Basic Energy Sciences user facility and also partially supported by the NNSA’s Laboratory Directed Research and Development Program.

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Authors

  • Y.M. Sheu

    • Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • S.A. Trugman

    • Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • L. Yan

    • Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • Q.X. Jia

    • Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • A.J. Taylor

    • Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • R.P. Prasankumar

    • Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA