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Density of States of a d-wave Superconductor in the Presence of Strong Impurity Scatterers: a Non Perturbative Result

Catherine Pepin·Patrick A. Lee
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Abstract

We present a method to compute the density of states induced by N non magnetic impurities in a d-wave superconductor, in the unitary limit of very strong scatering centers. For frequencies very small as compared to the superconducting gap ($ω\ll Δ_0$) the additional density of states has the leading divergence ${\displaystyle δρ(ω) \simeq n_i / [ | 2 ω| (\ln^2 |ω/Δ_0| + (π/2)^2)]}$. This result is non perturbative.

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Catherine Pepin, Patrick A. Lee. 2000-06-08. Density of States of a d-wave Superconductor in the Presence of Strong Impurity Scatterers: a Non Perturbative Result. https://doi.org/10.1103/physrevb.63.054502

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