Nanoscience Center, Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen, Denmark.
Department of Physics, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark.
Phys Rev Lett. 2013 Nov 27;111(22):227001. doi: 10.1103/PhysRevLett.111.227001. Epub 2013 Nov 25.
We present a combined magnetic neutron scattering and muon spin rotation study of the nature of the magnetic and superconducting phases in electronically phase separated La(2-x)Sr(x)CuO(4+y), x=0.04, 0.065, 0.09. For all samples, we find long-range modulated magnetic order below T(N) is approximately equal to Tc=39 K. In sharp contrast to oxygen-stoichiometric La(2-x)Sr(x)CuO(4), we find that the magnetic propagation vector as well as the ordered magnetic moment is independent of Sr content and consistent with that of the "striped" cuprates. Our study provides direct proof that superoxygenation in La(2-x)Sr(x)CuO(4+y) allows the spin stripe ordered phase to emerge and phase separate from superconducting regions with the hallmarks of optimally doped oxygen-stoichiometric La(2-x)Sr(x)CuO(4).
我们通过结合磁性中子散射和 muon 自旋旋转研究了电子相分离的 La(2-x)Sr(x)CuO(4+y)（x=0.04、0.065、0.09）中磁性和超导相的性质。对于所有样品，我们发现远距调制的磁有序低于 T(N)，大约等于 Tc=39K。与氧化学计量的 La(2-x)Sr(x)CuO(4)相比，我们发现磁传播矢量以及有序磁矩与 Sr 含量无关，与“条纹”铜酸盐一致。我们的研究提供了直接的证据，表明 La(2-x)Sr(x)CuO(4+y)中的超氧导致了自旋条纹有序相的出现，并与具有最佳掺杂氧化学计量的 La(2-x)Sr(x)CuO(4)的超导区域相分离。
