QuantaBull/qfabric-shield-classifier

QFabric Shield — Family Classifier (per-distance)

Lightweight transformer classifiers that ingest surface-code syndrome history and emit a softmax over four QFabric circuit families: {mps, grover, tebd, emu}. Used at runtime by the Shield dispatcher to route syndromes to the correct family-specialized decoder.

One classifier per code distance (input dimension scales with D).

Architecture

• 4-layer transformer encoder, d_model=128, 4 heads
• ~1M parameters
• Input: (B, 4, T, D, D) syndrome tensor
• Output: (B, 4) family logits

Distance variants

Each d{{N}}/ subdir contains the classifier trained at that distance.