Magnon-driven stochastic spin Hall nano-oscillators
Phys. Rev. Applied 25, 024051 – Published 17 February, 2026
DOI: https://doi.org/10.1103/1nym-hg7d
Abstract
Stochasticity in spintronic systems is crucial for neuromorphic and probabilistic computing applications. Systems such as low-barrier nanomagnets and magnetic tunnel junctions have shown stochastic behavior primarily driven by thermal noise; this limits their effectiveness at low temperatures. In this study, we demonstrate that spin Hall nano-oscillators (SHNOs) can efficiently exhibit inherent stochastic behavior independent of thermal noise, making them suitable for probabilistic computing and Ising machines. This stochasticity stems from energy dissipation through magnon propagation. We demonstrate that field-free SHNOs can display transient chaotic behavior. Further, we show that the observed stochasticity emerges from the transient chaos that has specific dependence on the excitation current values during oscillation mode transitions due to the induced spin wave instabilities. We present an application of such stochastic SHNOs for true random number generators in nanosecond time scale (∼20 ns) (in a simple configuration) and evaluate it with a statistical test suite (nist-sts). Our findings imply that SHNOs can be utilized for the development of efficient spintronic-based stochastic devices and novel computing paradigms, such as probabilistic computing.
