Mohottala Hashini E, Wells Barrett O, Budnick Joseph I, Hines William A, Niedermayer Christof, Udby Linda, Bernhard Christian, Moodenbaugh Arnold R, Chou Fang-Cheng
University of Connecticut U-3046, 2152 Hillside Road, Storrs, Connecticut 06269-3046, USA.
Nat Mater. 2006 May;5(5):377-82. doi: 10.1038/nmat1633. Epub 2006 Apr 16.
The complex interplay between superconducting and magnetic phases remains poorly understood. Here, we report on the phase separation of doped holes into separate magnetic and superconducting regions in superoxygenated La(2-x)Sr(x)CuO(4+y), with various Sr contents. Irrespective of Sr-doping, excess oxygen raises the superconducting onset to 40 K with a coexisting magnetic spin-density wave that also orders near 40 K in each of our samples. The magnetic region is closely related to the anomalous, 1/8-hole-doped magnetic versions of La(2)CuO(4), whereas the superconducting region is optimally doped. The two phases are probably the only truly stable ground states in this region of the phase diagram. This simple two-component system is a candidate for electronic phase separation in cuprate superconductors, and a key to understanding seemingly conflicting experimental observations.
超导相和磁相之间复杂的相互作用仍未得到很好的理解。在此，我们报道了在具有不同锶含量的超氧合La(2 - x)Sr(x)CuO(4 + y)中，掺杂空穴分离成单独的磁性区域和超导区域的相分离现象。无论锶掺杂情况如何，过量的氧将超导起始温度提高到40 K，同时伴随着一个共存的磁自旋密度波，在我们的每个样品中，该磁自旋密度波也在接近40 K时有序化。磁性区域与La(2)CuO(4)的反常的1/8空穴掺杂磁性变体密切相关，而超导区域是最佳掺杂的。这两个相可能是该相图区域中仅有的真正稳定的基态。这个简单的二元系统是铜酸盐超导体中电子相分离的一个候选者，也是理解看似相互矛盾的实验观测结果的关键。
