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تسجيل مستخدم جديدSticky Normal-Superconductor Interface
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We study the quantum Goos-H{a}nchen(GH) effect for wave-packet dynamics at a normal/superconductor (NS) interface. We find that the effect is amplified by a factor $(E_F/Delta)$, with $E_F$ the Fermi energy and $Delta$ the gap. Interestingly, the GH effect appears only as a time delay $delta t$ without any lateral shift, and the corresponding delay length is about $(E_F/Delta)lambda_F$, with $lambda_F$ the Fermi wavelength. This makes the NS interface sticky when $Delta ll E_F$, 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 $Delta$, 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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