1307.6032 (Jani Tuorila et al.)

Charge qubit driven via the Josephson nonlinearity    [PDF]

Jani Tuorila, Matti Silveri, Mika Sillanpää, Erkki Thuneberg, Yuriy Makhlin, Pertti Hakonen

We study the novel nonlinear phenomena that emerge in a charge qubit due to the interplay between a strong microwave flux drive and a periodic Josephson potential. We first analyze the system in terms of the linear Landau-Zener-St\"uckelberg model, and show its inadequacy in a periodic system with several Landau-Zener crossings within a drive period. Experimentally, we probe the quasienergy levels of the driven qubit with an LC-cavity, which requires the use of linear response theory. We also show that our numerical calculations are in good agreement with the experimental data.

View original: http://arxiv.org/abs/1307.6032