Theory of Macroscopic Quantum Dynamics in High-Tc Josephson Junctions

Shiro Kawabata

doi:10.1142/9789814282130_0050

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arXiv · 0912.4565

Theory of Macroscopic Quantum Dynamics in High-Tc Josephson Junctions

Shiro Kawabata

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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.

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Shiro Kawabata. 2009-12-23. Theory of Macroscopic Quantum Dynamics in High-Tc Josephson Junctions. https://doi.org/10.1142/9789814282130_0050

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