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arXiv:0912.4565 · Foundations of Quantum Mechanics in the Light of New Technology

THEORY OF MACROSCOPIC QUANTUM DYNAMICS IN HIGH-TC JOSEPHSON JUNCTIONS

Shiro Kawabata

Published Jun 1, 2009• 0 citations
arXivHTMLPDF

Abstract

We have theoretically investigated macroscopic quantum tunneling (MQT) and the influence of nodal quasiparticles and zero energy bound states (ZES) on MQT in s-wave/d-wave hybrid Josephson junctions. In contrast to d-wave/d-wave junctions, the low-energy quasiparticle dissipation resulting from nodal quasiparticles and ZES is suppressed due to a quasiparticle-tunneling blockade effect in an isotropic s-wave superconductor. Therefore, the inherent dissipation in these junctions is found to be weak. This result suggests high potential of s-wave/d-wave hybrid junctions for applications in quantum information devices.

DOI
10.1142/9789814282130_0050

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