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Ferroelectric switching and temperature-dependent electrical properties of K0.7Na0.3NbO3 capacitor devices

M. de Oliveira Guimaraes1,*, C. Richter1, J. Schwarzkopf1, M. Engl2, S. Slesazeck2, and M. Schmidbauer1

  • *Contact author: marilia.guimaraes@ikz-berlin.de
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Phys. Rev. Materials 10, 014413 – Published 27 January, 2026

DOI: https://doi.org/10.1103/ht3s-gvnm

Abstract

We performed the macroscopic electrical characterization of epitaxially grown, compressively strained K0.7Na0.3NbO3 thin films (70 nm) on SrRuO3/(110)TbScO3 substrates, displaying monoclinic Mc domains. Hysteresis measurements revealed ferroelectric behavior up to at least 107 cycles at room temperature, with a polarization value (2P) of 25µC/cm2. A double-peak switching behavior was observed, attributed primarily to domain-wall pinning/depinning and back switching, with a wake-up effect analogous to that reported in doped hafnium oxide and lead zirconate titanate systems. Temperature-dependent measurements (100 K—300 K) confirm ferroelectricity at low temperatures, while the double-peak behavior becomes less pronounced due to suppression of thermally activated back switching. Capacitance-voltage measurements reveal an increased dielectric response at higher temperatures, consistent with enhanced domain wall mobility. The asymmetry in coercive voltages additionally points to internal bias fields likely arising from electrode interfaces. Our results provide a comprehensive overview of the switching dynamics of strained K0.7Na0.3NbO3 films and demonstrate ferroelectricity in the Mc phase.

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Corrections

23 February, 2026

Correction: The author order was incorrect and has been fixed, which necessitated a change in the affiliation setup.

Article Text

Supplemental Material

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Outline

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Phys. Rev. Materials 10, 014413– Published 27 January, 2026
  • Received 1 October 2025
  • Revised 23 December 2025
  • Accepted 12 January 2026
  • Corrected 23 February 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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