Ferromagnetic properties of conducting filament nanodots formed on epitaxial BiFeO3 thin film

We investigate the ferromagnetic properties of the conducting filament (CF) nanodots formed on epitaxial BiFeO3 (BFO) thin film, which exhibit resistive switching behavior. 50nm thick epitaxial BFO thin film was grown on Nb-doped SrTiO3 single crystal substrates through pulsed laser deposition. The ferroelectric microcapacitor fabricated using the epitaxial BFO thin film shows excellent ferroelectric properties with a remanent polarization of approximately 32 mC/cm(2) and unipolar resistive switching behavior. CF nanodots with a diameter of approximately 16 nm are formed in the local region of the BFO thin film through conductive atomic force microscopy. Generally, ferromagnetic materials exhibit superparamagnetism, on a scale of tens of nanometers, as a result of the thermal energy of the magnetic moments. In this study, magnetic force microscopy demonstrates that the CF nanodot possesses ferromagnetism. It is suggested that exchange coupling between the CF nanodot and surrounding BFO causes the ferromagnetism of the nanodot. Our study provides new insight on the design of multistate memory cells with resistive switching and magnetic spin ordering, for application in high-density information storage media. (C)& nbsp;2022 The Author(s). Published by Elsevier B.V.& nbsp;

Automated summary

We investigate the ferromagnetic properties of conducting filament nanodots formed on epitaxial BiFeO3 thin film and provide new insights for the design of multistate memory cells with resistive switching and magnetic spin ordering.