Isotopic Topology as a Thermodynamically Unclonable Anchor for Supply Chain Security: Throughput Asymmetry Constraints in Non‑Equilibrium Metallic Gradients

The global semiconductor supply chain faces a growing risk from counterfeit components, recycled die, and hardware trojans that can bypass conventional digital cryptographic protections. This technical report introduces Isotopic Topology Authentication, a hardware assurance framework that encodes information in non-equilibrium gradients of stable nickel isotopes embedded within metallic interconnects. Because the isotopic gradients are chemically indistinguishable from standard interconnects yet require atom-by-atom serial assembly to clone, they form thermodynamically unclonable “physical anchors” tied to the original fabrication process. The report quantifies a throughput asymmetry of roughly 106–107 seconds for a cloning attempt versus less than one second for legitimate batch production, making counterfeiting economically irrational. Computational modeling further shows that these isotopic signatures are detectable in the field using handheld Laser-Induced Breakdown Spectroscopy (LIBS) with >99% confidence (Diso > 25) under 5% sensor noise, and Arrhenius analysis indicates stability exceeding 100 years at 85 °C. Together, these results support a depot-first deployment architecture in which logistics nodes authenticate “cold” (unpowered) chips before they enter critical defense and infrastructure systems.