arXiv:cond-mat/0205343 · Science

Manipulating the Quantum State of an Electrical Circuit

D. Vion, A. Aassime, Audrey Cottet, P. Joyez, H. Pothier, C. Urbina, D. Esteve, Michel Devoret

Published May 3, 2002• 1,625 citations

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 subcircuit. The measured quality factor of quantum coherence Qphi approximately 25,000 is sufficiently high that a solid-state quantum processor based on this type of circuit can be envisioned.

DOI: 10.1126/science.1069372

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