Quantum effects take over at the nanoscale, and classical simulators can’t see them. So Ciena’s analog team began building its own device models rather than relying only on supplied ones. Victory Atomistic, which solves the Poisson-Schrödinger equations self-consistently, met Ciena’s first requirements, and the two companies then worked together to extend it. For Ciena’s 5nm devices at room temperature, the simulated trends track lab data. Next comes qubit research, where simulation is meant to replace expensive cryogenic measurements. Convergence at the lowest temperatures and bias levels is still being improved.