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Ability of error correlations to improve the performance of variational quantum algorithms

J. Kattemölle and G. Burkard
Phys. Rev. A 107, 042426 (2023)

Selected as Editor's Suggestion.

The quantum approximate optimization algorithm (QAOA) has the potential of providing a useful quantum advantage on noisy intermediate-scale quantum (NISQ) devices. The effects of uncorrelated noise on variational quantum algorithms such as QAOA have been studied intensively. Recent experimental results, however, show that the errors impacting NISQ devices are significantly correlated. We introduce a…

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Fingerprints of Qubit Noise in Transient Cavity Transmission

P. M. Mutter, G. Burkard
Phys. Rev. Lett. 128, 236801 (2022)

Noise affects the coherence of qubits and thereby places a bound on the performance of quantum computers. We theoretically study a generic two-level system with fluctuating control parameters in a photonic cavity and find that basic features of the noise spectral density are imprinted in the transient transmission through the cavity. We obtain analytical expressions for generic noise and proceed to study the cases of quasistatic,…

The road to quantum computing

Our group is involved in the formation of three new research networks working on quantum computation–at the European level, at the federal level, and at the state level in Baden-Württemberg. Find out about the crucial challenges, the potential of silicon-based quantum bits, and the new research projects QLSI, QUASAR, QORA, and QC4BW here.