True random number generators (TRNGs) underpin modern cryptography, yet existing implementations face fundamental trade-offs between speed, scalability, and entropy quality. Here, we demonstrate that stochastic switching in the bistable regime of spin-wave dynamics provides a physical entropy source for high-quality random number generation. Our magnonic random number generator (mRNG), based on a lithography-patterned microstrip on yttrium iron garnet (YIG), exploits thermal fluctuations near the nonlinear bistable regime to generate random bitstreams that pass all 15 NIST SP 800-22 statistical tests at rates with 20 Mb/s. We implement a random-bit multiplier using synchronized mRNG units and demonstrate scalability to 200-nm-wide nanoscale waveguides, establishing spin-wave bistability as a viable physical entropy source for integrated random number generation.
@article{arxiv.2604.19356,
title = {True random number generation through stochastic magnonic bistability},
author = {Mengying Guo and Zhenyu Zhou and Denys Slobodianiuk and Roman Verba and Kristýna Davídková and Xueyu Guo and Xudong Jing and Yueqi Wang and Björn Heinz and Yiheng Rao and Carsten Dubs and Caihua Wan and Xiufeng Han and Andrii V. Chumak and Philipp Pirro and Qi Wang},
journal= {arXiv preprint arXiv:2604.19356},
year = {2026}
}