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arXiv · 1405.4360

Noise-enhanced synchronization of stochastic magnetic oscillators

Nicolas Locatelli·Alice Mizrahi·Artur Accioloy·Rie Matsumoto·Akio Fukushima·Hitoshi Kubota·Shinji Yuasa·Vincent Cros·Luis Gustavo Pereira·Damien Querlioz·Joo-Von Kim·Julie Grollier
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Abstract

We present an experimental study of phase-locking in a stochastic magnetic oscillator. The system comprises a magnetic tunnel junction with a superparamagnetic free layer, whose magnetization dynamics is driven with spin torques through an external periodic driving current. We show that synchronization of this stochastic oscillator to the input current is possible for current densities below $3 \times 10^6$ A/cm$^2$, and occurs for input frequencies lower than the natural mean frequency of the stochastic oscillator. We show that such injection-locking is robust and leads to a drastic reduction in the phase diffusion of the stochastic oscillator, despite the presence of a frequency mismatch between the oscillator and the excitation.

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Nicolas Locatelli, Alice Mizrahi, Artur Accioloy, Rie Matsumoto, Akio Fukushima, Hitoshi Kubota, Shinji Yuasa, Vincent Cros, Luis Gustavo Pereira, Damien Querlioz, Joo-Von Kim, Julie Grollier. 2014-05-17. Noise-enhanced synchronization of stochastic magnetic oscillators. https://arxiv.org/abs/1405.4360

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