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Manipulating the Quantum State of an Electrical Circuit

D. Vion·A. Aassime·A. Cottet·P. Joyez·H. Pothier·C. Urbina·D. Esteve·M. H. Devoret
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Abstract

We have designed and operated a superconducting tunnel junction circuit that behaves as a two-level atom: the ``quantronium''. An arbitrary evolution of its quantum state can be programmed with a series of microwave pulses, and a projective measurement of the state can be performed by a pulsed readout sub-circuit. The measured quality factor of quantum coherence Qphi=25000 is sufficiently high that a solid-state quantum processor based on this type of circuit can be envisioned.

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D. Vion, A. Aassime, A. Cottet, P. Joyez, H. Pothier, C. Urbina, D. Esteve, M. H. Devoret. 2002-05-29. Manipulating the Quantum State of an Electrical Circuit. https://doi.org/10.1126/science.1069372

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