Oscillating neural networks are promising candidates for a new computational paradigm, where complex optimization problems are solved by physics itself through the synchronization of coupled oscillating circuits. Nanoscale VO2 Mott memristors are particularly promising building blocks for such oscillating neural networks. Until now, however, not only the maximum frequency of VO2 oscillating neural networks, but also the maximum frequency of individual VO2 oscillators has been severely limited, which has restricted their efficient and energy-saving use. In this paper, we show how the oscillating frequency can be increased by more than an order of magnitude into the 100 MHz range by optimizing the sample layout and circuit layout. In addition, the physical limiting factors of the oscillation frequencies are studied by investigating the switching dynamics. To this end, we investigate how much the set and reset times slow down under oscillator conditions compared to the fastest switching achieved with single dedicated pulses. These results pave the way towards the realization of ultra-fast and energy-efficient VO2-based oscillating neural networks.
@article{arxiv.2506.01139,
title = {VO$_2$ oscillator circuits optimized for ultrafast, 100 MHz-range operation},
author = {Zsigmond Pollner and Tímea Nóra Török and László Pósa and Miklós Csontos and Sebastian Werner Schmid and Zoltán Balogh and András Bükkfejes and Heungsoo Kim and Alberto Piqué and Jeurg Leuthold and János Volk and András Halbritter},
journal= {arXiv preprint arXiv:2506.01139},
year = {2025}
}