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arXiv · 2509.13458

Tunable Random Telegraph Noise in Stable Perpendicular Magnetic Tunnel Junctions for Unconventional Computing

Ahmed Sidi El Valli·Michael Tsao·Dairong Chen·Andrew D. Kent
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Abstract

We demonstrate that thermally stable perpendicular magnetic tunnel junctions (pMTJs), widely used in spin-transfer torque magnetic random-access memory, can be actuated with nanosecond pulses to exhibit tunable stochastic behavior. This actuated-stochastic tunnel junction (A-sMTJ) concept produces random telegraph noise, with control over fluctuation rate and probability bias. The device response is shown to be consistent with a Poisson process, with fluctuation rates tunable over more than two orders of magnitude, with average state dwell times varying from 29 ns to greater than 2.3 microseconds. These results establish A-sMTJs as a versatile platform for integrating deterministic, stochastic, and in-memory functionality on a single chip, advancing the development of probabilistic, neuromorphic, and unconventional computing systems.

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Ahmed Sidi El Valli, Michael Tsao, Dairong Chen, Andrew D. Kent. 2025-09-16. Tunable Random Telegraph Noise in Stable Perpendicular Magnetic Tunnel Junctions for Unconventional Computing. https://doi.org/10.1103/tbm9-6938

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