Irena Spasojević, Federica Celegato, Alessandro Magni, P. Tiberto, Jordi Sort
ABSTRACT The Big Data revolution demands advanced security solutions that are energy‐efficient, scalable, and resistant to emerging threats. Conventional encryption, based on algorithmic complexity, is resource‐intensive and increasingly vulnerable. To safeguard sensitive information, it is essential to develop innovative anti‐hacking and anti‐counterfeiting technologies that provide material‐level protection embedded at the smallest length scales. Here, we present a selective magneto‐ionic strategy for hardware‐level security that exploits voltage‐controlled N 3– ion migration within pre‐defined paramagnetic FeCoN dot arrays. This enables the creation of reconfigurable sub‐15 nm ferromagnetic sublayers with deterministic or probabilistic (single‐domain↔vortex) states and voltage‐tunable probabilities. These states facilitate robust magnetic fingerprinting and constitute self‐protected primitives suitable for physical unclonable functions and in‐memory probabilistic inference, while their stochastic orientation and chirality provide a platform for true random number generation. This architecture combines tamper resistance, low power consumption, and scalability, representing a significant leap toward next‐generation hardware security rooted in ion‐spin control at the nanoscale.