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Detection of Geometric Phases in Superconducting Nanocircuits

Giuseppe Falci·Rosario Fazio·G. Massimo Palma·Jens Siewert·Vlatko Vedral
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Abstract

When a quantum mechanical system undergoes an adiabatic cyclic evolution it acquires a geometrical phase factor in addition to the dynamical one. This effect has been demonstrated in a variety of microscopic systems. Advances in nanotechnologies should enable the laws of quantum dynamics to be tested at the macroscopic level, by providing controllable artificial two-level systems (for example, in quantum dots and superconducting devices). Here we propose an experimental method to detect geometric phases in a superconducting device. The setup is a Josephson junction nanocircuit consisting of a superconducting electron box. We discuss how interferometry based on geometrical phases may be realized, and show how the effect may applied to the design of gates for quantum computation.

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Giuseppe Falci, Rosario Fazio, G. Massimo Palma, Jens Siewert, Vlatko Vedral. 2000-11-02. Detection of Geometric Phases in Superconducting Nanocircuits. https://doi.org/10.1038/35030052

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