Science

Making and manipulating a weak-link qubit

Jelena Stajic

Published Sep 10, 2015• 0 citations

Abstract

Mesoscopic Physics In superconductors, single particles cannot have energies smaller than the superconducting gap. Yet when two superconductors are separated by a thin nonsuperconducting bridge (the “weak link”), quasi-particles can occupy states that are inside the gap, the so-called Andreev bound states (ABSs). Janvier et al. fabricated such a structure out of superconducting aluminum and manipulated the occupation of a pair of ABSs. They observed oscillations in population between two of the energy levels, forming a type of qubit, which they dubbed the Andreev qubit. The results may lead to applications in quantum information processing. Science , this issue p. [1199][1] [1]: /lookup/doi/10.1126/science.aab2179

DOI: 10.1126/science.349.6253.1178-k

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