aiqbench takeQuantum Computing

Experiments on an IBM superconducting processor show that entanglement entropies after mid-circuit qubit resets track noiseless theory without fitted parameters, while concurrence, another entanglement measure, falls short of prediction on most runs. A depolarizing noise model accounts for that gap with one fitted parameter, so the hardware results are a useful check on how noise distorts different entanglement diagnostics. The work is a small-scale study (chains up to 12 qubits) and does not yet show an advantage for practical computation.

Source coveringQuantum Zeitgeist

Entanglement entropy matches predictions on IBM processor

Quantum ZeitgeistOctober 30, 20265 min read

Measurements on an IBM superconducting processor show the entropies evaluated before and after the reset average closely following noiseless predictions with no fitted parameter, while concurrence lies below prediction across most of the hardware measurements. They evaluated chains of up to 12 qubits exactly.

Researchers from the University of the Bundeswehr Munich and collaborating institutions have demonstrated that entropies measured on an IBM superconducting processor closely follow theoretical predictions without any fitted parameters. The work details how stochastic resetting, applying resets to qubits mid-circuit, creates unique, stable quantum states, and examines the resulting entanglement when reset histories are either tracked or averaged. These two diagnostics respond differently because they read different components of the same reconstructed state, and a depolarizing model captures the concurrence suppression with one fitted parameter. The difference between the two entropies, i. e., the Jensen gap, equals the Holevo information that…

Excerpt shown under the publisher's RSS terms · 101 words · full text and figures are on the publisher's site

Read at Quantum Zeitgeist ↗Ask about this article