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arXiv · 0906.0831

Fluxonium: single Cooper pair circuit free of charge offsets

Vladimir E. Manucharyan·Jens Koch·Leonid Glazman·Michel Devoret
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Abstract

The promise of single Cooper pair quantum circuits based on tunnel junctions for metrology and quantum information applications is severely limited by the influence of "offset" charges - random, slowly drifting microscopic charges inherent to many solid-state systems. By shunting a small junction with the Josephson kinetic inductance of a series array of large capacitance tunnel junctions, thereby ensuring that all superconducting islands are connected to the circuit by at least one large junction, we have realized a new superconducting artificial atom which is totally insensitive to offset charges. Yet, its energy levels manifest the anharmonic structure associated with single Cooper pair effects, a useful component for solid state quantum computation.

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Vladimir E. Manucharyan, Jens Koch, Leonid Glazman, Michel Devoret. 2009-06-04. Fluxonium: single Cooper pair circuit free of charge offsets. https://doi.org/10.1126/science.1175552

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