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arXiv · 0806.3149

Microwave Penetration Depth and Quasiparticle Conductivity in PrFeAsO_1-y Single Crystals : Evidence for a Full-Gap Superconductor

K. Hashimoto·T. Shibauchi·T. Kato·K. Ikada·R. Okazaki·H. Shishido·M. Ishikado·H. Kito·A. Iyo·H. Eisaki·S. Shamoto·Y. Matsuda
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Abstract

In-plane microwave penetration depth $λ_{ab}$ and quaiparticle conductivity at 28 GHz are measured in underdoped single crystals of the Fe-based superconductor PrFeAsO$_{1-y}$ ($T_c\approx 35$ K) by using a sensitive superconducting cavity resonator. $λ_{ab}(T)$ shows flat dependence at low temperatures, which is incompatible with the presence of nodes in the superconducting gap $Δ({\bf k})$. The temperature dependence of the superfluid density demonstrates that the gap is non-zero ($Δ/k_BT_c\gtrsim 1.6$) all over the Fermi surface. The microwave conductivity below $T_c$ exhibits an enhancement larger than the coherence peak, reminiscent of high-$T_c$ cuprate superconductors.

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K. Hashimoto, T. Shibauchi, T. Kato, K. Ikada, R. Okazaki, H. Shishido, M. Ishikado, H. Kito, A. Iyo, H. Eisaki, S. Shamoto, Y. Matsuda. 2008-12-11. Microwave Penetration Depth and Quasiparticle Conductivity in PrFeAsO_1-y Single Crystals : Evidence for a Full-Gap Superconductor. https://doi.org/10.1103/physrevlett.102.017002

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