Three-qubit bit-flip code
Protect one logical qubit by spreading it across three physical qubits.
Back to learning pathQuantum information applicationsWhy this experiment matters
What you will do
See how ideal majority correction changes independent physical X-error risk into logical-error risk.
- 01
Encode α|0⟩+β|1⟩ across three qubits.
- 02
Let each physical qubit flip independently with probability p.
- 03
Use ideal parity checks and majority correction.
04 · PREDICT
Predict before you measure
Choose one answer to unlock the measurement.
INTERACTIVE
Interactive model
Move the control, then run a measurement. This is a teaching simulation—not hardware output.
Make a prediction, then run the measurement to reveal the expected and sampled results.
Measurement results
What the result shows
The logical error is 3p²−2p³. The code improves reliability below 50% physical error, but makes it worse above 50%.
GUIDED VIDEO
Watch the experiment
Follow the experiment with English narration and English subtitles.
See how ideal majority correction changes independent physical X-error risk into logical-error risk.
Full transcript5 · 1:00
- 01Overview
See how ideal majority correction changes independent physical X-error risk into logical-error risk.
- 02Experiment steps 1
Encode α|0⟩+β|1⟩ across three qubits.
- 03Experiment steps 2
Let each physical qubit flip independently with probability p.
- 04Experiment steps 3
Use ideal parity checks and majority correction.
- 05What to observe
The logical error is 3p²−2p³. The code improves reliability below 50% physical error, but makes it worse above 50%.
06 · CHECK
Check what you learned
Make a prediction, then run the measurement to reveal the expected and sampled results.