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Title: Voltage-activated parametric entangling gates based on gatemon qubits
We describe the generation of entangling gates on superconductor-semiconductor hybrid qubits by ac voltage modulation of the Josephson energy. Our numerical simulations demonstrate that the unitary error can be below 10−5 in a variety of 75-ns-long two-qubit gates (CZ, 𝑖⁢SWAP, and √𝑖⁢SWAP) implemented using parametric resonance. We analyze the conditional 𝑍⁢𝑍 phase and demonstrate that the CZ gate needs no further phase-correction steps, while the 𝑍⁢𝑍 phase error in swap-type gates can be compensated by choosing pulse parameters. With decoherence considered, we estimate that qubit relaxation time needs to exceed 70μ⁢s to achieve the 99.9% fidelity threshold.  more » « less
Award ID(s):
2244274
NSF-PAR ID:
10525719
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
American Physical Society
Date Published:
Journal Name:
Physical Review Applied
Volume:
20
Issue:
4
ISSN:
2331-7019
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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