Generating quantum entanglement is plagued by decoherence.
Distillation and error-correction are employed against such noise, but designing a good distillation circuit, especially on today’s imperfect hardware, is challenging.
Researchers have developed a simulation algorithm for distillation circuits with per-gate complexity of O(1) , drastically faster than O(N) Clifford simulators or O(2N) wavefunction simulators over N qubits.
This simulator made it possible to optimize distillation circuits much larger than previously feasible.
They designed distillation circuits from n raw Bell pairs to k purified pairs and studied the use of these circuits in the teleportation of logical qubits.
The resulting purification circuits are the best-known for finite-size noisy hardware and can be fine-tuned for specific error-models.
Furthermore, they designed purification circuits that shaped the correlations of errors in the purified pairs such that the performance of potential error-correcting codes was greatly improved.
npj Quantum Information, Published online: 23 January 2025; doi:10.1038/s41534-024-00948-0