2023/03/30 by Hamid Sakhouf, Mohammed Daoud, M. Daoud +2
Computer Science · Physics and Astronomy · #Quantum Information and Cryptography #Quantum Computing Algorithms and Architecture #Quantum Mechanics and Applications
paper · doi:10.1088/1361-6455/acc916
Abstract A single-shot entangling gate plays a crucial role in quantum information processing due to its high fidelity. This operation gate is fast to create a maximally entangled state and forms a universal gate set for quantum computing. Currently, the preparation and demonstration of multi-qubit entanglement are achieved based on sequences of single- and two-qubit operations, yielding lower fidelity and requiring longer execution time. Here, we demonstrate by numerically simulating the use of quantum process tomography to fully characterize the performance of a single-shot three-qubit entangling gate. This gate is used to create a Greenberger–Horne–Zeilinger entangled state in Sakhouf et al (2021 J. Phys. B: At. Mol. Opt. Phys. 54 175501), directly generated by three transmon-type superconducting qubits which are mediated by a resonator with the assistance of a microwave field. Comparing ideal and simulated quantum process tomography, we characterize the entangling gate performance by calculating the mean fidelity achieving a high value <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mo>≻</mml:mo> </mml:mrow> <mml:mn>0.93</mml:mn> </mml:math> .