Work

Time-Optimal Two- and Three-Qubit Gates for Rydberg Atoms

Year: 2022

Type: article

Abstract: We identify time-optimal laser pulses to implement the controlled-Z gate and its three qubit generalization, the C 2 Z gate, for Rydberg atoms in the blockade regime. Pulses are optimized using a combination of numerical and semi-analytical quantum optimal control techniques that result in smooth Ansätze with just a few variational parameters. For the CZ gate, the time-optimal implementation corresponds to a global laser pulse that does not require single site addressability of the atoms, simplifying experimental implementation of the gate. We employ quantum optimal control techniques to mitigate errors arising due to the finite lifetime of Rydberg states and finite blockade strengths, while several other types of errors affecting the gates are directly mitigated by the short gate duration. For the considered error sources, we achieve theoretical gate fidelities compatible with error correction using reasonable experimental parameters for CZ and C 2 Z gates.

Source: Quantum

DOI: 10.22331/q-2022-05-13-712

Authors: Sven Jandura, Guido Pupillo

Institutions: Centre National de la Recherche Scientifique, Institut de Science et d'Ingénierie Supramoléculaires, Université de Strasbourg

Language: English

Topic: Quantum Computing Algorithms and Architecture

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $215

Funders: European Commission, Agence Nationale de la Recherche, Université de Strasbourg, Institut Universitaire de France