CSNSM, Université Paris-Sud and CNRS/IN2P3, 91405 Orsay cedex, France.
Phys Rev Lett. 2011 May 13;106(19):197002. doi: 10.1103/PhysRevLett.106.197002. Epub 2011 May 9.
We report on laser-excited angle-resolved photoemission spectroscopy in the electron-doped cuprate Sm1.85Ce0.15CuO(4-δ). The data show the existence of a nodal hole-pocket Fermi surface both in the normal and superconducting states. We prove that its origin is long-range antiferromagnetism by an analysis of the coherence factors in the main and folded bands. This coexistence of long-range antiferrmagnetism and superconductivity implies that electron-doped cuprates are two-Fermi-surface superconductors. The measured superconducting gap in the nodal hole pocket is compatible with a d-wave symmetry.
我们报告了在电子掺杂的铜酸盐 Sm1.85Ce0.15CuO(4-δ) 中进行的激光激发角分辨光电子能谱研究。数据表明，在正常态和超导态下都存在节点空穴口袋费米面。我们通过对主带和折叠带中的相干因子的分析证明了其起源是长程反铁磁序。这种长程反铁磁序与超导共存表明，电子掺杂铜酸盐是具有两个费米面的超导体。在节点空穴口袋中测量到的超导能隙与 d 波对称性相兼容。
