  Stochastic devices have the potential to disrupt computing, revolutionizing
low-power machine learning acceleration, probabilistic computing, and hardware
security. As implemented, however, superparamagnetic tunnel junctions (sMTJs)
face significant challenges including the need for external magnetic fields,
and poor reliability and scalability. Here, we present experimental
demonstration of three-terminal sMTJs as scalable and reliable sources of true
randomness under a field-free regime. By leveraging dual-current
controllability and incorporating feedback systems, we substantially enhance
the stability and reliability of sMTJ-based systems under varying conditions,
even in the field-free regime. Our findings demonstrate the generation of
cryptographic-quality random bitstreams and the practical use of sMTJs as
efficient and reliable random number generators, successfully integrated into
advanced computing algorithms like generative artificial intelligence.
Field-free, truly random sMTJs promise to address critical challenges in
cryptography, edge computing, and beyond, significantly advancing the field of
random number generation.
