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arXiv · 0901.1419

Theory of tunnelling into a multi-band superconductor: decoherence and interference

Da Wang·Yuan Wan·Qiang-Hua Wang
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Abstract

By an exact formulation of tunnelling into a multi-band superconductor in terms of Green's functions, we demonstrate that the multi-band feature of the iron-based superconductors can lead to novel interference between Andreev reflections and decoherence effect of quasi-particles to Andreev reflections in a tunnelling junction. These effects depend on the relative sign of the gaps for s-wave pairing, and the sign of the Fermi velocities also matters for tunnelling along the nodal direction of d-wave gaps. Experimental probe of such effects could determine both the pairing symmetry and the relative sign of the gaps on different bands.

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Da Wang, Yuan Wan, Qiang-Hua Wang. 2009-01-11. Theory of tunnelling into a multi-band superconductor: decoherence and interference. https://doi.org/10.1103/physrevlett.102.197004

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