Control qubit: superposition
Photon (solid = collapsed) Ghost — coherent dual path Port A detector Port B detector
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Quantum-Controlled Photonic Switch

A classical optical switch reads a control voltage that is always definitely 0 or 1 and routes light to one of two ports accordingly. This simulator swaps that voltage for a control qubit. Prepared in |0⟩ or |1⟩ it behaves exactly like the classical case — deterministic routing, every time. Prepared in an adjustable superposition, the photon instead becomes entangled with the qubit and travels a coherent superposition of both output paths until a measurement collapses it, with the resulting port statistics tracking cos²(θ/2) / sin²(θ/2) and the qubit's final state always correlating with the detected port — the signature of entanglement-based routing rather than classical randomness.