Sticky Normal-Superconductor Interface

Soo-Young Lee; Arseni Goussev; Orestis Georgiou; Goran Gligoric; Achilleas Lazarides

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arXiv · 1212.6188

Sticky Normal-Superconductor Interface

Soo-Young Lee·Arseni Goussev·Orestis Georgiou·Goran Gligoric·Achilleas Lazarides

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Abstract

We study the quantum Goos-Hänchen(GH) effect for wave-packet dynamics at a normal/superconductor (NS) interface. We find that the effect is amplified by a factor $(E_F/Δ)$, with $E_F$ the Fermi energy and $Δ$ the gap. Interestingly, the GH effect appears only as a time delay $δt$ without any lateral shift, and the corresponding delay length is about $(E_F/Δ)λ_F$, with $λ_F$ the Fermi wavelength. This makes the NS interface "sticky" when $Δ\ll E_F$, since typically GH effects are of wavelength order. This "sticky" behavior can be further enhanced by a resonance mode in NSNS interface. Finally, for a large $Δ$, the resonance-mode effect makes a transition from Andreev to the specular electron reflection as the width of the sandwiched superconductor is reduced.

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Soo-Young Lee, Arseni Goussev, Orestis Georgiou, Goran Gligoric, Achilleas Lazarides. 2012-12-26. Sticky Normal-Superconductor Interface. https://arxiv.org/abs/1212.6188

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