In situ impedance matching in Nb/Nb2O5/PtIr memristive nanojunctions for ultra-fast neuromorphic operation

Dániel Molnár, Tímea Nóra Török, Botond Sánta, Agnes Gubicza, András Magyarkuti, Roland Hauert, Gábor Kiss, András Halbritter, Miklós Csontos

Research output: Article

2 Citations (Scopus)

Abstract

The dynamical aspects of bipolar resistive switchings have been investigated in Nb/Nb2O5/PtIr nanojunctions. We found that the widely tuneable ON and OFF state resistances are well separated at low bias. On the other hand, the high-bias regime of the resistive switchings coincides with the onset of a high nonlinearity in the current-voltage characteristics, where the impedance of both states rapidly decreases and becomes equivalent around 50 Ω. This phenomenon enables the overriding of the RC limitations of fast switchings between higher resistance ON and OFF states. Consequently, nanosecond switching times between multiple resistance states due to subnanosecond voltage pulses are demonstrated. Moreover, this finding provides the possibility of impedance engineering by the appropriate choice of voltage signals, which facilitates that both the set and reset transitions take place in an impedance matched manner to the surrounding circuit, demonstrating the merits of ultra-fast operation of Nb2O5 based neuromorphic networks.

Original languageEnglish
Pages (from-to)19290-19296
Number of pages7
JournalNanoscale
Volume10
Issue number41
DOIs
Publication statusPublished - nov. 7 2018

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ASJC Scopus subject areas

  • Materials Science(all)

Cite this

Molnár, D., Török, T. N., Sánta, B., Gubicza, A., Magyarkuti, A., Hauert, R., Kiss, G., Halbritter, A., & Csontos, M. (2018). In situ impedance matching in Nb/Nb2O5/PtIr memristive nanojunctions for ultra-fast neuromorphic operation. Nanoscale, 10(41), 19290-19296. https://doi.org/10.1039/c8nr06226a