Perturbative analysis of quasiperiodic patterning of transmon quantum computers: Enhancement of many-body localization

To be useful for quantum computation, qubits in an array must remain localized -- that is, not ``dressed'' too much by nearby degrees of freedom. This localization has been previously achieved using disorder. But the authors observe here that a more effective route to localization is with a quasiperiodic patterning of the qubit array Hamiltonian. This paper develops two different perturbation approaches to calculate diagnostics for many-body localization in quasiperiodic superconducting transmon arrays. Perturbing in anharmonicity versus perturbing in hopping strength give complementary information.