Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada. Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada. Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany. Quantum Materials Program, Canadian Institute for Advanced Research, Toronto, Ontario M5G 1Z8, Canada.
Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada. Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
Science. 2015 Jan 16;347(6219):282-5. doi: 10.1126/science.1256441.
In cuprate high-temperature superconductors, an antiferromagnetic Mott insulating state can be destabilized toward unconventional superconductivity by either hole or electron doping. In hole-doped (p-type) cuprates, a charge ordering (CO) instability competes with superconductivity inside the pseudogap state. We report resonant x-ray scattering measurements that demonstrate the presence of charge ordering in the n-type cuprate Nd(2-x)Ce(x)CuO4 near optimal doping. We find that the CO in Nd(2-x)Ce(x)CuO4 occurs with similar periodicity, and along the same direction, as in p-type cuprates. However, in contrast to the latter, the CO onset in Nd(2-x)Ce(x)CuO4 is higher than the pseudogap temperature, and is in the temperature range where antiferromagnetic fluctuations are first detected. Our discovery opens a parallel path to the study of CO and its relationship to antiferromagnetism and superconductivity.
在铜酸盐高温超导体中，反铁磁莫特绝缘态可以通过空穴或电子掺杂而向非常规超导态失稳。在空穴掺杂（p 型）铜酸盐中，电荷有序（CO）不稳定性与赝能隙态中的超导性竞争。我们报告了共振 X 射线散射测量结果，证明了在近最佳掺杂的 n 型铜酸盐 Nd(2-x)Ce(x)CuO4 中存在电荷有序。我们发现 Nd(2-x)Ce(x)CuO4 中的 CO 具有与 p 型铜酸盐相似的周期性，并沿着相同的方向。然而，与后者不同的是，Nd(2-x)Ce(x)CuO4 中的 CO 起始温度高于赝能隙温度，并且处于首次检测到反铁磁涨落的温度范围内。我们的发现为研究 CO 及其与反铁磁性和超导性的关系开辟了一条平行途径。
