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Infrared Signature of the Superconducting State in Pr(2-x)Ce(x)CuO(4)

A. Zimmers·R. P. S. M. Lobo·N. Bontemps·C. C. Homes·M. C. Barr·Y. Dagan·R. L. Greene
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Abstract

We measured the far infrared reflectivity of two superconducting Pr(2-x)Ce(x)CuO(4) films above and below Tc. The reflectivity in the superconducting state increases and the optical conductivity drops at low energies, in agreement with the opening of a (possibly) anisotropic superconducting gap. The maximum energy of the gap scales roughly with Tc as 2 Delta_{max} / kB Tc ~ 4.7. We determined absolute values of the penetration depth at 5 K as lambda_{ab} = (3300 +/- 700) A for x = 0.15 and lambda_{ab} = (2000 +/- 300) A for x = 0.17. A spectral weight analysis shows that the Ferrell-Glover-Tinkham sum rule is satisfied at conventional low energy scales \~ 4 Delta_{max}.

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A. Zimmers, R. P. S. M. Lobo, N. Bontemps, C. C. Homes, M. C. Barr, Y. Dagan, R. L. Greene. 2004-05-13. Infrared Signature of the Superconducting State in Pr(2-x)Ce(x)CuO(4). https://doi.org/10.1103/physrevb.70.132502

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