Measurement of a fluxonium qubit embedded in a waveguide

The fluxonium qubit in a 3D cavity has been shown to have energy relaxation times of order 1 ms. The qubit readout contrast, however, was only approximately 10 degrees. High qubit readout contrast and fast operations on a qubit state are necessary ingredients for any implementation of a quantum computer. We have designed and measured a fluxonium qubit embedded in a waveguide in order to achieve these goals. We present measurements of the dispersive shift on a Josephson junction resonator inductively coupled to the fluxonium qubit as well as the relaxation times of the fluxonium qubit in this new architecture.