Science

This Week in Science

Published Jun 6, 2003• 0 citations

Abstract

Superconducting quantum bits (qubits) are currently being developed as promising candidates for implementations in quantum computers. Although the quality of single qubits has been improving with coherence times sufficiently long to allow manipulation of the states of the qubit, the ability to couple, or entangle, qubits together will be required for quantum computing to be realized. Taking initial steps along this route, Berkley et al. (p. 1548) entangled two macroscopic quantum systems, current-biased Josephson junctions, that were separated by 0.7 millimeters but coupled via capacitors. Spectroscopic studies show that the electronic energy levels correspond to those expected for entanglement of the two qubits.

DOI: 10.1126/science.2003.300.5625.twis

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