Memristive devices are hardware components for applications in neuromorphic computing, memories, and logic computation. This work contributes to the ongoing debate on the switching mechanism of eightwise polarity in SrTiO3‐based resistive switches. Specifically the effect of atmospheric humidity on the materials defect chemistry and switching properties is considered. Asymmetric devices are designed by exchanging the top and bottom positions of Pt and LaNiO3electrodes allowing for a separate analysis of the top and the bottom metal‐oxide interfaces. Under dry atmospheres the switching hysteresis is enhanced with a top Pt contact and suppressed with a bottom Pt contact. It is argued that the buried position and dense microstructure of the bottom platinum impedes an oxygen vacancy driven switching mechanism. Under humid atmospheres eightwise switching occurs in both devices suggesting the presence of two switching mechanisms within the same eightwise switching polarity, namely, oxygen vacancy and hydroxide ion enabled switching. The findings help develop strategies to suppress eightwise switching by burying the active metal‐oxide interface and ensuring dense electrode microstructures. Suppression of switching mechanisms relying on exchange with the environment is desirable for technological implementation of resistive switches and for strategies in stacking of memristive devices for memory and for neuromorphic hardware.
Polarization of ionic and electronic defects in response to high electric fields plays an essential role in determining properties of materials in applications such as memristive devices. However, isolating the polarization response of individual defects has been challenging for both models and measurements. Here the authors quantify the nonlinear dielectric response of neutral oxygen vacancies, comprised of strongly localized electrons at an oxygen vacancy site, in perovskite oxides of the form
- PAR ID:
- 10366656
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 9
- Issue:
- 4
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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