• Alff, Lambert
• Komissinskiy, Philipp
• Major, Marton
• Cardoletti, Juliette
• Schneider, Thorsten
• Ding, Hui
• Jiang, Tianshu
• Molina-Luna, Leopoldo
• Zhang, Mao-Hua

Abstract

<jats:p> An antipolar phase is confirmed for NaNbO<jats:sub>3</jats:sub> thin films grown by pulsed laser deposition on SrTiO<jats:sub>3</jats:sub> (100) substrates. Reciprocal space maps and transmission electron microscopy reveal the presence of characteristic 1/4 superlattice reflections, indicative of the antipolar displacement of Na and Nb-ions. Furthermore, x-ray diffraction unveils the presence of two different orientations of the same phase for thin films beyond a critical thickness of about 60 nm. This orientation change with increasing thickness can be explained as an extraordinary strain compensation mechanism, changing magnitude and sign of the strain at the same time. The polarization vs electric field behavior exposes a characteristic thickness dependence, with the antiferroelectric phase stabilized for very thin films and a field induced ferroelectric hysteresis for a film of 310 nm having a maximum polarization of 26.5  μC [Formula: see text], which is among the highest values reported for NaNbO<jats:sub>3</jats:sub> thin films grown on SrTiO<jats:sub>3</jats:sub> (100). </jats:p>

Topics

• impedance spectroscopy
• phase
• x-ray diffraction
• thin film
• transmission electron microscopy
• pulsed laser deposition