Spin-Based True Random Number Generation Enabled by Voltage-Amplified Quantum Fluctuations

TL;DR

This paper explores how voltage-controlled amplification of quantum spin fluctuations in magnetic tunnel junctions can be used to develop a new type of spin-based true random number generator, grounded in microscopic quantum dynamics.

Contribution

It introduces a microscopic framework linking quantum spin fluctuations with voltage-controlled magnetic anisotropy for random number generation.

Findings

Quantum fluctuations dominate magnetization dynamics at certain temperatures.

Voltage amplification exponentially increases spin quantum fluctuations.

Magnetoresistance enables binary readout for random number generation.

Abstract

We investigate spin quantum-fluctuation effects that originate from the Heisenberg uncertainty principle during the dynamical cycle of disentanglement, entanglement, and re-disentanglement between itinerant electrons and localized magnetic moments mediated by the s-d exchange interaction. Beyond conventional deterministic spin-transfer torque, we analyze an intrinsic mechanism that transfers spin quantum fluctuations to a nanomagnet. By extending the Landau-Lifshitz-Gilbert equation to incorporate both quantum and thermal stochastic fields, we identify a temperature regime in which quantum fluctuations dominate the magnetization dynamics. We further show that voltage-controlled magnetic anisotropy exponentially amplifies spin quantum fluctuations, enabling binary readout through magnetoresistance in magnetic tunnel junctions. These findings provide a microscopic framework for fluctuation-driven spin dynamics and outline a device-level pathway toward spin-based quantum true random number generation.