A New Flux/Phase Qubit With Integrated Readout
Maria Gabriella Castellano, F. Chiarello, Roberto Leoni, G. Torrioli, P. Carelli, C. Cosmelli, M. DiBucchianico, F. Mattioli, Stefano Poletto, Daniela Simeone · IEEE Transactions on Applied Superconductivity · 2005
We propose a new scheme for a flux/phase qubit, based on a double-SQUID modified to achieve a direct readout of the flux state. The readout is performed by inserting a large Josephson junction in the SQUID loop; the junction is biased by an external current and switches from the zero-voltage to the running state depending on the flux state of the qubit. We report recent results concerning the theoretical behavior and the experimental characterization at 4.2 K of the device, which has been realized with Nb/AlOx/Nb trilayer technology.