Establish a unified microscopic account of interface-to-filamentary switching

Establish a detailed microscopic understanding of the processes that drive the transition from interface-type to filamentary-type switching in TiN/SiOx/Cu/SiOx/TiN memristive devices, and describe that transition within a unified simulation framework.

Background

The paper uses separate effective one-dimensional cloud-in-a-cell frameworks to reproduce interface-type and filamentary-like switching responses. The filamentary model introduces phenomenological rules for vacancy binding, filament formation, and rupture, rather than resolving the atomistic or three-dimensional transition from distributed interfacial switching to localized conduction.

The authors identify the microscopic origin of this transition as insufficiently understood and explicitly leave its detailed physical description for future work. Resolving it would enable a unified model capable of predicting both switching modes without adding mode-specific phenomenological modifications.

References

However, the microscopic processes that drive the transition from interface-type to filamentary-type switching are still not sufficiently understood. A more detailed physical understanding of this transition, and its eventual description within a unified simulation framework, therefore remains an important topic for future work.

— On the physical origins of switching diversity in Cu-embedded SiO$_x$ memristive devices  (2609.10799 - Yarragolla et al., 9 Sep 2026) in Conclusion

Despite these individual findings, the holistic causal multiscale relationship between deposition conditions, atomistic defect formation, Cu redistribution after deposition, and macroscopic functionality is unclear both qualitatively and quantitatively.

— From Processing to Functionality: Engineering Accessible Material States in Cu-Embedded SiO$_x$ Memristive Devices  (2609.30047 - Gergs et al., 24 Sep 2026) in Introduction, Sections 1 and 1.1

Together, these observations link growth-induced defect topology to copper redistribution and, ultimately, the formation of electrically active internal states, although the underlying atomistic transport mechanisms remain to be resolved.

— From Processing to Functionality: Engineering Accessible Material States in Cu-Embedded SiO$_x$ Memristive Devices  (2609.30047 - Gergs et al., 24 Sep 2026) in Discussion, Section 4