This preprint presents a "Topological Firewall" for secure free-space quantum communication. We propose repurposing controlled unmagnetized dusty plasmas — typically a source of decoherence in QKD — as a dynamic Physical Unclonable Function (PUF) and intrusion detection layer. The architecture leverages Orbital Angular Momentum (OAM) eigenmodes, where precise topological charge l l l matching authenticates signals. Eavesdropping or mismatched states disturb the helical phase front, producing detectable entropy slope spikes (ΔS/Δt S / t ΔS/Δt) and topological charge drift. A Hybrid Kinetic-Informed QNN controller, using latent 6D phase-space embeddings and Hamiltonian constraints, monitors these signatures in real time and triggers autonomous handoff abortion in the Spyder v2 routing protocol. Controlled dust charging and lofting via the Patched Charge Model (PCM-SP), modulated OAM beams, and Universal Optical Trapping enable tunable plasma configurations. The system converts known challenges — dusty-channel QBER degradation and accelerator dust-induced beam losses — into a deterministic security asset. Applications focus on trusted-node-free quantum routing for secure smart grid infrastructure. Table-top validation using GEC Reference Cells, spatial light modulators, and standard diagnostics is outlined. This work bridges plasma physics, quantum optics, and AI, providing a physical-layer enhancement to existing QKD protocols while maintaining full kinetic awareness through latent embeddings.
Venerable et al. (Fri,) studied this question.