arXiv:2402.09145 · Physical Review Applied

Lattice Hamiltonians and stray interactions within quantum processors

Xuexin Xu, Manabputra, Chloé Vignes, Mohammad H. Ansari, John M. Martinis

Published Dec 10, 2024• 7 citations

Abstract

This study's modeling of superconducting quantum processors reveals that, contrary to popular belief, three-body ZZZ stray couplings can surpass parasitic ZZ interactions, posing a serious threat to gate fidelity and crosstalk. Even more striking, strongly decoupled qubits---long thought to be ideal---can be more problematic than loosely coupled ones, even when idle. These findings overturn traditional design principles and force us to rethink next-generation architectures for quantum processors.

DOI: 10.1103/physrevapplied.22.064030

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