Long-Range Incommensurate Charge Fluctuations in (Y,Nd)Ba2Cu3O6+x
Long-Range Incommensurate Charge Fluctuations in (Y,Nd)Ba2Cu3O6+x
复制标题
DOI：
10.1126/science.1223532
复制
发表时间：
2012-08-17
期刊：
影响因子：
56.9
通讯作者：
Braicovich, L.
中科院分区：
文献类型：
--
作者：
Ghiringhelli, G.;Le Tacon, M.;Braicovich, L.
超导性与铜酸盐超导体中的其他有序竞争的概念已经变得越来越明显，但用体敏感探针获得直接证据是具有挑战性的。我们已经使用共振软X-射线散射，以确定二维电荷波动的超导体（Y，Nd）Ba 2Cu 3 O 6 +x的铜氧化物平面中的3.2晶格单元类似的不相称的周期性，与孔浓度为0.09至0.13每个平面铜离子。当冷却到超导转变温度（Tc）时，波动信号的强度和相关长度会强烈增加;进一步冷却到Tc以下会突然逆转电荷相关的发散。结合早期观察到的自旋激发光谱中的大间隙，这些数据表明一个初期的电荷密度波不稳定性，与超导性竞争。
The concept that superconductivity competes with other orders in cuprate superconductors has become increasingly apparent, but obtaining direct evidence with bulk-sensitive probes is challenging. We have used resonant soft x-ray scattering to identify two-dimensional charge fluctuations with an incommensurate periodicity of similar to 3.2 lattice units in the copper-oxide planes of the superconductors (Y,Nd)Ba2Cu3O6+x, with hole concentrations of 0.09 to 0.13 per planar Cu ion. The intensity and correlation length of the fluctuation signal increase strongly upon cooling down to the superconducting transition temperature (T-c); further cooling below T-c abruptly reverses the divergence of the charge correlations. In combination with earlier observations of a large gap in the spin excitation spectrum, these data indicate an incipient charge density wave instability that competes with superconductivity.