Controlled filament stability in SrTiO3 memristors via swift Xe ion irradiation

Abstract

Due to uncontrolled conductive filament (CF) formation and rupture during operation, CF randomness in SrTiO3-based memristors severely limits their stability and retention. To address this challenge, we employ swift heavy ion (SHI) irradiation—516 MeV Xe ions—on Pt/SrTiO3/Nb:SrTiO3 devices, introducing controlled ion track defects that guide filament formation. The irradiated memristors demonstrate remarkable performance improvements, achieving a lower SET voltage of 0.65 V (compared to 0.85 V for unirradiated devices), extended retention (>106 s vs <105 s), and superior stability (σ/μ = 0.06/0.06 vs 0.14/0.04). Moreover, these devices reliably emulate synaptic plasticity with minimal cycle-to-cycle variations (<7.2%), enabling high-fidelity neuromorphic applications. When deployed in simulated neural networks for handwritten digit recognition, the irradiated memristors attain a recognition accuracy of 91.6%, showcasing their robustness in real-time computing tasks. These results highlight SHI irradiation as an effective strategy to engineer defect-guided pathways in oxide memristors, advancing their applicability in stable, high-performance neuromorphic systems.