https://doi.org/10.1140/epjp/s13360-022-02561-6
Regular Article
Protection of qubits by nonlinear resonances
1
Department of Physics and Astronomy, Macquarie University, 2122, Sydney, NSW, Australia
2
Nuclear Physics Division, Bhabha Atomic Research Centre, 400085, Mumbai, India
3
Theoretical Nuclear Physics & Quantum Computing Section, Nuclear Physics Division, Bhabha Atomic Research Centre, 400085, Mumbai, India
4
Homi Bhabha National Institute, 400094, Mumbai, India
5
UM-DAE Centre for Excellence in Basic Sciences, Vidyanagari Campus, 400098, Mumbai, India
Received:
27
September
2021
Accepted:
2
March
2022
Published online:
17
March
2022
We show that quantized superconducting circuits are non-integrable at the classical level of description, adorned by nonlinear resonances amidst stochastic sea. The stable (elliptic) and unstable (hyperbolic) points occur in a way that by choosing the parameters of a system close to elliptic points, the dynamics is stable. Quantum mechanically, any disturbance has to tunnel the separatrix to reach the elliptic point. Thus, nonlinearity of the system provides protection. Based on these fundamental considerations from the Kolmogorov–Arnold–Moser theorem, we propose criteria for protection of qubits from any disturbance.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2022
