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Quantum Zeno effect in the Cooper-pair transport through a double-island Josephson system

Alexander Shnirman·Yuriy Makhlin
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Abstract

Motivated by recent experiments, we analyze transport of Cooper pairs through a double-island Josephson qubit. At low bias in a certain range of gate voltages coherent superpositions of charge states play a crucial role. Analysis of the evolution of the density matrix allows us to cover a wide range of parameters, incl. situations with degenerate levels, when dissipation strongly affects the coherent eigenstates. At high noise levels the so-called Zeno effect can be observed, which slows down the transport. Our analysis explains certain features of the I-V curves, in particular the visibility and shape of resonant peaks and lines.

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Alexander Shnirman, Yuriy Makhlin. 2003-11-08. Quantum Zeno effect in the Cooper-pair transport through a double-island Josephson system. https://doi.org/10.1134/1.1633315

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