Polarization-dependent PL

Why. A quantum dot’s bright exciton is split into two lines polarized at right angles — the fine-structure splitting (FSS). It decides whether the dot can emit entangled photon pairs, so it is measured on every candidate dot. The splitting is usually smaller than the linewidth: it shows only as a tiny swing of the line’s centre while the analysed polarization turns, read over a whole sweep of spectra. That is one plate move, one position check and one exposure per angle, ninety angles per dot — the work this experiment does unattended.

What it measures. For each dot, one spectrum per angle of a half-wave plate in front of a fixed polarizer:

What it analyzes. After a dot’s last angle, the FineStructure analyzer of plesty-fss fits every line in every spectrum, then a sine to each line’s centre against the angle: its peak-to-peak is the FSS, its phase the polarization axis — see Analysis.

uv sync
uv run python -m plesty.pol_pl --dry-run                       # the plan, no devices
uv run python -m plesty.pol_pl --config config/default.yaml    # run

Page	Shows
Setup	the devices, the plan, what to set and configure
Running	start it, the demo, drive and watch a run, what it writes
Analysis	each numbered box above, what it reports, how to read it