Nanoscale Ring-Shaped Conduction Channels with Memristive Behavior in BiFeO3 Nanodots

Abstract

Nanoscale ring-shaped conduction channels with memristive behavior have been observed in the BiFeO3 (BFO) nanodots prepared by the ion beam etching. At the hillside of each individual nanodot, a ring-shaped conduction channel is formed. Furthermore, the conduction channels exhibit memristive behavior, i.e., their resistances can be continuously tuned by the applied voltages. More specifically, a positive (negative) applied voltage reduces (increases) the resistance, and the resistance continuously varies as the repetition number of voltage scan increases. It is proposed that the surface defects distributed at the hillsides of nanodots may lower the Schottky barriers at the Pt tip/BFO interfaces, thus leading to the formation of ring-shaped conduction channels. The surface defects are formed due to the etching and they may be temporarily stabilized by the topological domain structures of BFO nanodots. In addition, the electron trapping/detrapping at the surface defects may be responsible for the memristive behavior, which is supported by the surface potential measurements. These nanoscale ring-shaped conduction channels with memristive behavior may have potential applications in high-density, low-power memory devices.

Electrolyte-Dependent Modification of Resistive Switching in Anodic Hafnia

“…This directly relates to different behaviors between anodic memristors thermally treated or formed in different electrolytes. It was previously reported that the switching mechanism may also refer to an electron trapping/detrapping from the Pt interface which can increase or lower the Schottky barrier, thus reducing or increasing the CFs conductance [ 49 ]. Additionally, in the present work, the CFs were influenced by electrolyte species incorporation.…”

Uniform arrays of centre-type topological domains in epitaxial ferroelectric thin films

“…With the extension of time, that is, the increase of pulse width, as a positive electric field is applied, the defect ions (positive V O s) in the film gradually enrich downward, resulting in the formation of a built-in electric field. 52,53 The direction of the built-in electric field is opposite to that of the external one, which weakens the size of the total electric field, as shown in Fig. 5(d).…”

Center‐Type Topological Domain States in Ferroelectric Nanodots Tailored from Thin Films

“…[ 5,11,17–19 ] Furthermore, the study of the fabrication of BiFeO 3 (BFO) nanostructures with strain has shown that the eight polarization variants of the rhombohedral BFO cell, geometry constraints, and strain tuning are conducive to forming topological defects. [ 20–24 ]…”

“…[5,11,[17][18][19] Furthermore, the study of the fabrication of BiFeO 3 (BFO) nanostructures with strain has shown that the eight polarization variants of the rhombohedral BFO cell, geometry constraints, and strain tuning are conducive to forming topological defects. [20][21][22][23][24] However, quantitative experimental investigations of the exotic domain states are needed for smaller nanodots, which require piezoresponse force microscopy (PFM). PFM detects the local vibration of ferroelectric samples, which is caused by the application of AC voltage between an atomic force microscope (AFM) tip and the bottom electrode in a sample.…”