Source

engines/design23_v1/package/design23_recentered_optimizer/multilayer_nanobeam_phase10/README.md · assembled 2026-07-29 15:57 UTC.

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Multilayer nanobeam — Phase 10

The feedthrough pole is continued from the validated real-frequency mode to complex s = omega / omega_reference. At each Newton step, the non-Hermitian Dyson eigenpair is selected by overlap with the preceding right vector. The left/right eigenvectors give the exact complex-beta Laurent residue. The negative pole and residue follow from reciprocity rather than a second solve.

This continuation is required before a complex-frequency cavity pole can be trusted: simply scaling the real feed beta would corrupt both the port phase and the external linewidth.