Functional Perovskite Superlattices

Abstract

Abstract People Publications

K. Boldyreva, L. Pintilie, A. Lotnyk, I. B. Misirlioglu, N. D. Zakharov, M. Alexe, D. Hesse

Epitaxial antiferroelectric/ferroelectric PbZrO₃/PbZr_0.8Ti_0.2O₃ (PZO/PZT) superlattices were grown on SrRuO₃-electroded SrTiO₃(100) substrates by pulsed laser deposition. Polarization-field and switching current-voltage curves show a mixed antiferroelectric-ferro­electric behavior of the superlattices with an individual layer thickness above 10 nm, whereas below 10 nm the superlattices show only ferroelectric behavior. Clearly the PbZrO₃ layers thinner than 10 nm experienced a transition into the ferroelectric state. X-ray diffraction reciprocal space mapping showed a corresponding orthorhombic-to-rhombohedral transi­tion of the PbZrO₃ layers.

Fig. 1: Cross section high-resolution TEM image of a coherently grown strained PZO/PZT superlattice with an individual layer thickness of 6 nm.

Fig. 2: Macroscopic polarization hysteresis curve of two superlattices with 100 nm overall thickness each. t – thickness of the individual layers. Blue: Loop with mixed antiferroelectric-ferroelectric character. Green: Loop with only ferroelectric character.

For details see Applied Physics Letters 91 (2007) 122915.