Photonic MOC

Curated map of Zoo entries in the Photonic family.

Entries

Entry	Type	Status
dual-rail-photonic-qubit	qubit	demonstrated
fusion-based-photonic-qubit	qubit	proposed
linear-optical-photonic-qubit	qubit	demonstrated
photonic-cluster-state-mbqc-qubit	qubit	demonstrated
photonic-qubit	qubit	demonstrated
time-bin-photonic-qubit	qubit	demonstrated

Composition

• qubit: 6

Curated synthesis

The highest-value organizing move in this family is to separate photonic encodings from photonic computation models. Otherwise the graph quietly conflates “what degree of freedom stores the qubit?” with “how do we actually get entangling power and fault tolerance?”

1. Encodings optimized for different physical routes

   • dual-rail-photonic-qubit is the canonical chip-scale / LOQC encoding when spatial modes and integrated interferometers are the native hardware language.
   • time-bin-photonic-qubit is the fiber-native encoding when long-distance stability and network transport matter more than on-chip rail geometry.
   • These should be read together through erasure-error-vs-pauli-error and noise-bias-and-asymmetric-error-channels: both are loss-dominated photonic qubits, but they package phase stability constraints very differently.

2. Gate-based linear optics is an architecture, not an encoding

   • linear-optical-photonic-qubit is the KLM lineage: minimal interactions, heavy ancilla and feed-forward overhead.
   • It usually rides on encodings like dual-rail-photonic-qubit, but the conceptual payload is architectural: probabilistic optics plus teleportation still clear the threshold-theorem barrier in principle.

3. Resource-state / measurement-first photonics is the modern scaling branch

   • photonic-cluster-state-mbqc-qubit shifts the burden from online gates to offline cluster-state preparation plus adaptive measurement.
   • fusion-based-photonic-qubit goes one step further and treats failed entangling attempts as an architectural primitive rather than an exception.
   • Both belong in the same fault-tolerance conversation because they live or die on whether loss and fusion failures stay structured enough for erasure-aware decoding and percolation-style thresholds.

Where the umbrella note belongs

• photonic-qubit should be the family entry point, not a peer competitor to the more specific notes. Use it when the question is simply why photons are attractive at all: low transport decoherence, room-temperature optics, and natural network compatibility.
• Hand off from photonic-qubit to dual-rail-photonic-qubit or time-bin-photonic-qubit when the real comparison is the encoding degree of freedom.
• Hand off from photonic-qubit to linear-optical-photonic-qubit, photonic-cluster-state-mbqc-qubit, or fusion-based-photonic-qubit when the real comparison is the scaling architecture.
• Once the question stops being optical-hardware-specific and becomes, “what does flagged loss buy the decoder?”, cross over to cross-platform-moc through erasure-qubit instead of repeating decoder logic inside this family.

Editorial note

The next highest-value follow-up is a dedicated evergreen note on the photonic split between encoding choice (dual-rail vs time-bin) and scaling strategy (KLM vs MBQC vs fusion), but the current pass is enough to stop photonic-qubit from floating as an undifferentiated umbrella note.