Multiplexed dispersive readout of superconducting phase qubits

Yu Chen; D. Sank; P. O'Malley; T. White; R. Barends; B. Chiaro; J. Kelly; E. Lucero; M. Mariantoni; A. Megrant; C. Neill; A. Vainsencher; J. Wenner; Yi Yin; A. N. Cleland; John M. Martinis

doi:10.1063/1.4764940

arXiv · 1209.1781

Multiplexed dispersive readout of superconducting phase qubits

Yu Chen·D. Sank·P. O'Malley·T. White·R. Barends·B. Chiaro·J. Kelly·E. Lucero·M. Mariantoni·A. Megrant·C. Neill·A. Vainsencher·J. Wenner·Yi Yin·A. N. Cleland·John M. Martinis

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Abstract

We introduce a frequency-multiplexed readout scheme for superconducting phase qubits. Using a quantum circuit with four phase qubits, we couple each qubit to a separate lumped-element superconducting readout resonator, with the readout resonators connected in parallel to a single measurement line. The readout resonators and control electronics are designed so that all four qubits can be read out simultaneously using frequency multiplexing on the one measurement line. This technology provides a highly efficient and compact means for reading out multiple qubits, a significant advantage for scaling up to larger numbers of qubits.

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Yu Chen, D. Sank, P. O'Malley, T. White, R. Barends, B. Chiaro, J. Kelly, E. Lucero, M. Mariantoni, A. Megrant, C. Neill, A. Vainsencher, J. Wenner, Yi Yin, A. N. Cleland, John M. Martinis. 2012-09-09. Multiplexed dispersive readout of superconducting phase qubits. https://doi.org/10.1063/1.4764940

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