# 2022 Color Center Entanglement

## Scope

This is a self-contained reveal.js deck for a pedagogical QNT meeting talk, "Noisy Entanglement (on Color Centers)," by Stefan Krastanov at MIT on Jul 15, 2022. `HEADER.md` describes it as a talk on entanglement generation and distillation in color centers and embeds `presentation.html`.

There are no immediate talk-version subfolders here. The immediate subdirectories are reveal.js support folders such as `dist/` and `plugin/`.

## Entry Points

- `presentation.html`: the actual deck.
- `HEADER.md`: archive metadata and iframe preview.

## Content Themes

- Introductory entanglement material using Alice/Bob qubits and Bell-state labels `A`, `B`, `C`, and `D`.
- Hidden-variable/contextuality context via `art_installation.mp4`.
- Color-center hardware split into optical electronic spin for networking and microwave/nuclear spin for memory.
- Entanglement-generation protocols: DLCZ-like low-probability success, Barrett-Kok path erasure, single-photon reflection, and Duan-Kimble atom-photon gates.
- Protocol comparison by rate, classical-light requirements, optical excitation, spectral diffusion, charge-state instability, and hyperfine-memory concerns.
- Noisy entanglement purification, simple purification circuits, error propagation, probability reshuffling, and coincidence measurements.
- Evolutionary optimization of purification circuits, optimized entanglement-purification results, the `qevo.krastanov.org` iframe, hardware constraints, and QuantumClifford.jl / QuantumSavory.jl tools.

## Assets And Patterns

- Main local assets include `alice.png`, `bob.png`, `art_installation.mp4`, `color_centers.png`, `color_centers_nuclear.png`, `DLCZ-*.png`, `BK.png`, `reflection-based.png`, `Duan-Kimble.png`, `simple_purify*.png`, `error_prop.png`, `pur_gates.png`, `mutation.png`, `offspring.png`, `L17_and_STRINGENT_shaded_named.png`, `purify_opt_results.png`, and `c15fixed_pretty.png`.
- The deck uses reveal.js black theme, local `custom.css`, KaTeX math, fragments, vertical slide stacks, `data-auto-animate`, fixed-bottom `ol.bib` citations, and inline styles for slide-specific sizing.
- `custom.css` provides `.flex-h`, `figure`, `.bib`, `.border`, `.border-bottom`, plus `.bc0`-`.bc9` and `.c0`-`.c9` math/text highlight classes.

## Editing Guidance

- Edit `presentation.html` and local assets. Do not edit vendored reveal.js files under `dist/` or `plugin/`.
- Preserve the self-contained relative paths for local images and videos.
- Keep Bell-state labels and purification notation consistent across the intro and purification sections.
- The `qevo.krastanov.org` slide depends on an external iframe; if making an offline-only version, replace it with a local screenshot or explicitly note the dependency.
- For content review, run `../tools/reveal_text.py presentation.html --max-chars 30000` from this folder.