Microwave Penetration Depth and Quasiparticle Conductivity of PrFeAsO1-y Single Crystals: Evidence for a Full-Gap Superconductor
Microwave Penetration Depth and Quasiparticle Conductivity of PrFeAsO1-y Single Crystals: Evidence for a Full-Gap Superconductor
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DOI：
10.1103/physrevlett.102.017002
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发表时间：
2009-01-09
影响因子：
8.6
通讯作者：
Matsuda, Y.
中科院分区：
文献类型：
--
作者：
Hashimoto, K.;Shibauchi, T.;Matsuda, Y.
用灵敏的超导谐振腔测量了欠掺杂铁基超导体PrFeAsO_（1-y）单晶（Tc约为35 K）在28 GHz处的面内微波穿透深度λ（ab）和准粒子电导率。λ（ab）（T）在低温下表现出平坦的依赖性，这与超导能隙Delta（k）中节点的存在不相容。超流密度的温度依赖性表明，在整个费米面上，差距都是非零的（Delta/k（B）T（c）大于或接近1.6）。低于T-c的微波电导率表现出比相干峰更大的增强，这让人想起高T-c铜酸盐超导体。
In-plane microwave penetration depth lambda(ab) and quasiparticle conductivity at 28 GHz are measured in underdoped single crystals of the Fe-based superconductor PrFeAsO1-y (T-c approximate to 35 K) by using a sensitive superconducting cavity resonator. lambda(ab)(T) shows flat dependence at low temperatures, which is incompatible with the presence of nodes in the superconducting gap Delta(k). The temperature dependence of the superfluid density demonstrates that the gap is nonzero (Delta/k(B)T(c)greater than or similar to 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.