Magnetic-field-induced ferroelectric domain dynamics and in-plane polarization in odd and mixed layered Aurivillius structures

Abstract

Herein, we conclusively discovered the role of “2D” odd/mixed, layered Aurivillius structures in generating coupled order parameters by directly visualizing magnetic-field-induced ferroelectric switching. We developed a novel sequence liquid injection-chemical vapor deposition process to fabricate atomistically controlled layer-by-layer genuine multiferroic Bi6Ti2.9Fe1.5Mn0.6O18 and Bi6Ti2.7Fe1.5Mn0.8O18 thin films. Ferromagnetic signature (MS = 13.79 emu/cc, HC = 9 mT at 300 K, and MR = 8 emu/cc) was generated for Bi6Ti2.9Fe1.5Mn0.6O18 thin films; however, no response was observed for mixed m = 5/6 intergrowths in Bi6Ti2.7Fe1.5Mn0.8O18 films. In-plane PR with magnetic (Fe/Ti)/conducting (Au/Ti) for Bi6Ti2.9Fe1.5Mn0.6O18 thin films is less (±23.66–24.69 μC/cm2) than the mixed m = 5/6 Bi6Ti2.7Fe1.5Mn0.8O18 layer structure (±57.42–67.94 μC/cm2). High leakage current for Fe/Ti interdigital capacitors (IDCs) compared to Au/Ti IDCs samples confirms Au/Ti IDCs’ suitability for ferroelectric industry. High ferro-paraelectric transition (Tc = 850 K), excellent in-plane polarization with negligible fatigue (9% after 1010 switching cycles), and coupled magnetoelectric (ME) (10% in-plane and 13% out-of-plane) orders provide an important contribution in a high-temperature fatigue free nonvolatile in-plane FeRAM, 4-state logics, and ME sensors. This article is being retracted effective 16 November 2020.