Polarizing-Depolarizing fields competition on PbTiO$_3$ nanocapacitors

ORAL

Abstract

We analyzed the stability of various interfacial atomic arrangements in PbTiO$_3$ (PTO) based nanocapacitors, using density functional theory (DFT). We observed that particular constructions induce a large polarization enhancement via a net field depolarizing-to-polarizing swap within the PTO layers, as revealed by analysis of electrostatic potential profiles. In contrast to those with a dominant depolarizing field, possessing a polarization below that of the bulk, the polar structures are stable in the thin-film regime. Interface atomic relaxation is also observed to be a key factor in determining the overall stability of the different capacitor configurations. This boosted charge screening capacity along with appropriate engineering of the interface chemistry, are potential how-to pointers to alleviate the critical thickness in ferroelectric-based nanocapacitors.

*The authors acknowledge financial and computational support from ONR, DoE and DoD.

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Authors

  • Miguel Angel Mendez Polanco

    • University of Pennsylvania, Department of Chemistry

  • Ilya Grinberg

    • University of Pennsylvania
    • The Makineni Theoretical Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA
    • University of Pennsylvania, Department of Chemistry

  • Andrew Rappe

    • University of Pennsylvania
    • The Makineni Theoretical Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA
    • Department of Chemistry, University of Pennsylvania
    • Makineni Theoretical Laboratories, Department of Chemistry, University of Pennsylvania
    • University of Pennsylvania, Department of Chemistry