Walkthrough ‐ Quantum III.D: Distillary

Learning Objectives

• The player is challenged to transform a given entangled state on three qubits into a maximally entangled state (Bell pair) on two qubits. To do so players must properly understand the wavefunction collapse when a single qubit from an entangled state is measured.
• This level serves as an introduction to entanglement distillation, which is employed in several later levels.

Solution

1. The bottom qubit is measured in the Z basis.
2. If the measurement result was a 0 then the remaining two qubits are kept (as it is known that they are in a maximally entangled state), else they are incinerated.
3. A final flip gate is applied to transform the entangled state into a Bell pair.

Level File (copy then paste into Qubit Factory)

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