100 nm SiN atom-strip first-step seed-width sweep#
Status: complete · progress: 11 / 11 widths complete · updated: 2026-09-05 14:20 UTC
This controlled sweep asks only how the first temporal-gradient seed changes when the immutable atom-access strip is moved from 1.0 to 2.0 µm. Every point starts independently from density 0.5; no geometry or optimizer state is carried from one width to the next.
The common stack is a 100 nm SiN film embedded between 300 nm of SiO2 per side, with SiO2 filling the complete x-y plane (including x/y PML) and air outside the finite stack in z. The physical design region is 12 × 4 µm and the retained simulation uses x/y/z symmetry with an Ey atom response. The hard air strip cuts through the complete SiO2/SiN stack.
The reported objective gain is not inferred from the gradient. It is measured by a fresh forward replay after the single raw-Adam update.
Download the numerical sweep table · Read the exact method · Compare with the 300 nm SiN sweep
air strip (µm) |
J before |
J after replay |
ΔJ |
fidelity after |
dominant lag (µm) |
correlation peak |
|---|---|---|---|---|---|---|
1.0 |
-0.896661 |
-0.886168 |
0.010493 |
0.530176 |
0.25 |
0.75 |
1.1 |
-0.890217 |
-0.879247 |
0.0109698 |
0.532128 |
0.25 |
0.7785 |
1.2 |
-0.893688 |
-0.881725 |
0.0119627 |
0.531427 |
0.25 |
0.78 |
1.3 |
-0.906972 |
-0.893989 |
0.0129833 |
0.527986 |
0.25 |
0.8025 |
1.4 |
-0.925854 |
-0.911901 |
0.0139533 |
0.52304 |
0.25 |
0.8005 |
1.5 |
-0.947361 |
-0.932506 |
0.0148556 |
0.517463 |
0.25 |
0.8118 |
1.6 |
-0.97036 |
-0.954752 |
0.0156081 |
0.511574 |
0.25 |
0.8033 |
1.7 |
-0.993566 |
-0.977438 |
0.0161285 |
0.505705 |
0.25 |
0.8078 |
1.8 |
-1.01487 |
-0.998465 |
0.016406 |
0.500384 |
0.25 |
0.7986 |
1.9 |
-1.03203 |
-1.01575 |
0.016282 |
0.496094 |
0.25 |
0.7919 |
2.0 |
-1.0445 |
-1.02908 |
0.0154252 |
0.492835 |
0.3 |
0.783 |
Objective comparison#
Updated geometries#
The density panels use the physical 0-to-1 scale. Because this is exactly one step from 0.5, the second atlas is the more sensitive view of the emerging seed.
Geometry differences#
Longitudinal regularity telemetry#
Interpretation guardrails#
Larger \(J\) (less negative) and positive \(\Delta J\) mean a better match to the fixed ideal waveform.
The density-change panels compare the actual first Adam moves. Fixed air and feedthrough pixels remain unchanged.
The autocorrelation peak is descriptive only. It summarizes repetition in the complete two-dimensional update and does not rank, select, or modify a seed.