Source

engines/quan_loncar_v1/package/quan_loncar_optimizer/engine/quan_loncar_series_phase30/README.md · assembled 2026-07-29 15:57 UTC.

---

Quan--Loncar series, Phase 30

Phase 30 batches the validated moving-pole derivative over every packed hole parameter. Four contour traversals assemble the base branch, the geometry contractions needed by the eigenvector and residue derivatives without materializing one dense operator derivative per parameter. Multi-right-hand-side bordered solves then return the complete Jacobian of the pole, Q, point Green residue, and complex/effective mode volume.

FullGeometryObjectiveJacobian.objective_pullback(...) is the framework-neutral custom-VJP boundary: real cotangents for Q, effective mode volume, normalized mode volume, and resonance coordinates are combined into one geometry cotangent. A JAX/PyTorch wrapper only needs to cache this result and return the pullback; it must not differentiate through Newton or the eigensolver.