title: Readout of superconducting flux qubit state with a Cooper pair box.
abstract: We study a readout scheme of a superconducting flux qubit state with a Cooper pair box as a transmon. The qubit states consist of the superpositions of two degenerate states where the charge and phase degrees of freedom are entangled. Owing to the robustness of the transmon against external fluctuations, our readout scheme enables the quantum non-demolition and single-shot measurement of flux qubit states. The qubit state readout can be performed by using the nonlinear Josephson amplifiers after a π/2 rotation driven by an ac electric field.
authors.affiliation: Institute of Physics and Applied Physics, Yonsei University, Seoul, Korea. mdkim@yonsei.ac.kr
authors.forename: Mun Dae
authors.initials: MD
authors.lastname: Kim
authors.forename: K
authors.initials: K
authors.lastname: Moon