⚛ QECLab — Interactive Quantum Error Correction Laboratory

The first interactive browser-based laboratory for understanding quantum error correction (QEC). Explore surface codes, inject errors, compare decoders, and discover the threshold theorem — all with zero dependencies.

6 Interactive Modules

1. Surface Code Builder

Explore the rotated surface code architecture — the leading candidate for fault-tolerant quantum computing. Visualize data qubits, X/Z stabilizer plaquettes, and boundary conditions for code distances 3–9.

2. Error Injection & Syndrome Extraction

Click to inject Pauli X, Z, or Y errors on data qubits and watch syndrome extraction in real-time. See which stabilizers trigger and whether the error pattern is correctable.

3. Decoder Arena

Compare three decoding algorithms side-by-side:

• MWPM (Minimum Weight Perfect Matching) — the gold-standard decoder
• Union-Find — near-linear-time approximate decoder
• Greedy — fastest but least accurate

Each decoder runs on the same error pattern with step counts and success/failure indicators. Includes batch accuracy comparison over 200 random trials.

4. Threshold Explorer

Monte Carlo simulation of the threshold theorem — the most important result in QEC. Watch logical error rate curves for d=3,5,7,9 converge at the ~1% threshold. Run up to 5000 samples per point.

5. Logical Qubit Visualizer

Interactive 3D Bloch sphere showing the encoded logical qubit state. Apply fault-tolerant gates (X, Z, H, S, T), see error clouds, and compare fidelity with/without error correction. Drag to rotate.

6. Code Zoo

Compare 5 major QEC code families: Surface, Steane [[7,1,3]], Shor [[9,1,3]], Toric, and Color codes. Visual structure diagrams, properties table, and historical timeline from Shor (1995) to NVIDIA Ising (2026).

Why QEC Matters (April 2026)

Quantum error correction is THE frontier topic in quantum computing:

• NVIDIA Ising — first open AI model family for QEC decoding (2026)
• Google AlphaQubit — ML-powered QEC achieving state-of-the-art decoding
• Microsoft Azure Quantum — QEC development tools in QDK
• EdenCode — startup achieving sub-millisecond AI decoding

Tech Stack

• Single HTML file (~2300 lines)
• Vanilla JS + Canvas API
• Zero external dependencies
• Works offline

Run Locally

# Just open it
open index.html
# Or serve it
python -m http.server 8000

License

MIT — Built with Claude Code as part of the Daily Webapp project.