Persistent 780 nm production optimization

Live decision

The full-vector fixed-frequency atom-coupling campaign is authorized and runs without a preset iteration count. Its current state, retained-step count, centered-emitter response, exact invariants, Q status, and spectral progress are published on the live dashboard.

The optimizer uses configs/fullvector_atom_780_production_refined.json:

• wavelength 780 nm and normalized frequency 1.0;
• grid 40 x 70 x 28;
• 235,200 physical vector unknowns reduced to 29,499 by the qualified component-correct x/y/z symmetry sector;
• immutable one-wavelength opening |x| < 0.5 lambda0;
• centered z-dipole LDOS as the primary objective;
• adaptive trust-region learning rate starting at 0.004, bounded to 0.00025--0.064, with up to six halvings during backtracking.

Persistent iteration protocol

Each topology iteration is a fail-closed direct sequence:

1. carry the exact same-grid topology variables and density only;
2. discard all saved fields and solve a fresh 780 nm primal/adjoint pair;
3. compare the exact log-LDOS gain with the gradient's predicted gain and require an Armijo ratio of at least 0.25, in addition to the direct response, field identity, localization, PML energy, protected air, reflection, extrusion, frequency, and wavelength gates;
4. save the retained topology as a new immutable step directory;
5. mark the retained checkpoint provisional unless it is a scheduled Q validation step.

The trust radius doubles after a first-try accepted step whose realized versus predicted log-gain ratio is at least 0.75. Any failed scientific or Armijo gate halves the proposal until it passes or reaches the declared minimum. The requested, attempted, accepted, and next learning rates, agreement ratio, and failed gates are retained in every step record and shown on the dashboard. This searches for the largest locally trustworthy step instead of leaving the campaign pinned to the 0.001 launch-gate trial.

The exact 0.995--1.005 spectrum at 81 fixed frequencies and seven independent complex probes runs at iterations 10, 20, 30, .... The partially completed step-3 sweep from the original every-step protocol is also completed and kept as an extra validated checkpoint. The dashboard always distinguishes direct gate passage from Q validation and reports the iteration of the last valid Q diagnostic.

If a scheduled exact diagnostic still finds analytic background, Q is reported as no in-window pole. If a physical pole candidate appears, topology updates pause before assigning Q. The nonlinear pole and same-basis mode must then be reacquired and validated on that checkpoint.

Stop and restart behavior

An operator stop preserves every completed step and any partial 81-point spectrum. Restarting resumes the first incomplete step and reuses only exact frequency samples belonging to its declared grid. A rejected topology is not promoted. Any nonzero protected-air density or reflection/extrusion violation stops the campaign.

All intermediate topology checkpoints are retained. If a scheduled sweep finds a pole, the intervening provisional checkpoints can be backfilled to locate its first appearance before any resonance claim is made.

The optimizer process and the static-site publisher run separately, so solver progress remains checkpointed even if documentation publication is temporarily unavailable.

The topology close-up outlines the exact mutable x/y mask with translucent rectangles; the one-wavelength central gap and fixed interface slices are not inside those overlays. A separate full-device view places the retained defect between four explicit periodic mirror cells on each side. Dashed lead interfaces mark where the displayed defect couples to the DtN self-energies; arrows indicate that those mirrors continue semi-infinitely in the solved model even though only representative periods can be drawn.

Progress through 2026-08-18

Steps 4 through 15 passed every direct acceptance gate. Step 10's scheduled Q diagnostic completed with holdout NRMSE 5.59e-13 and no physical lower-half-plane pole in the target window. Adaptive steps 11--15 then tested and accepted 0.004, 0.008, 0.016, 0.032, and 0.064 on their first trials; their predicted/realized log-gain ratios remained between 0.888 and 1.017. At retained step 15, the centered-emitter LDOS is 1718.5305, a 1.149930x (+14.993%) gain over the production baseline. Same-basis field overlap is 0.997511, gap energy is 0.789419, and PML energy is 0.067070. The protected-air, reflection-symmetry, and z-extrusion errors remain exactly zero. Steps 11--15 remain provisional until the scheduled step-20 Q diagnostic.

The first attempt to start step 10 stopped because the supervisor read the optimizer's JSON status file while that file was being rewritten. This was an operator-monitoring failure, not a solver or scientific-gate failure; step 10 had not produced or promoted a topology. Status publication is now atomic and the supervisor retries transient JSON reads. The campaign resumes from the intact step-9 density-only checkpoint; the recovered step-10 validation and subsequent adaptive steps are recorded above.

Claim boundary

This campaign searches for improved emitter coupling and the creation of a physical 780 nm resonance. Until a pole appears and passes nonlinear, cross-basis, grid, and domain gates, the result is not a resonant-cavity Q, Purcell factor, useful-port beta factor, tweezer-scattering budget, fabrication-ready structure, or device claim.