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arXiv · 1409.5647

Multiplexed Readout of Transmon Qubits with Josephson Bifurcation Amplifiers

V. Schmitt·X. Zhou·K. Juliusson·A. Blais·P. Bertet·D. Vion·D. Esteve
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Abstract

Achieving individual qubit readout is a major challenge in the development of scalable superconducting quantum processors. We have implemented the multiplexed readout of a four transmon qubit circuit using non-linear resonators operated as Josephson bifurcation amplifiers. We demonstrate the simultaneous measurement of Rabi oscillations of the four transmons. We find that multiplexed Josephson bifurcation is a high-fidelity readout method, the scalability of which is not limited by the need of a large bandwidth nearly quantum-limited amplifier as is the case with linear readout resonators.

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V. Schmitt, X. Zhou, K. Juliusson, A. Blais, P. Bertet, D. Vion, D. Esteve. 2014-10-24. Multiplexed Readout of Transmon Qubits with Josephson Bifurcation Amplifiers. https://doi.org/10.1103/physreva.90.062333

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