Grafe H-J, Curro N J, Hücker M, Büchner B
Condensed Matter and Thermal Physics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Phys Rev Lett. 2006 Jan 13;96(1):017002. doi: 10.1103/PhysRevLett.96.017002. Epub 2006 Jan 3.
We report 17O nuclear-magnetic-resonance (NMR) results in the stripe ordered La(1.8-x)Eu0.2Sr(x)CuO4 system. Below a temperature T(q) approximately 80 K, the local electric field gradient and the absolute intensity of the NMR signal of the planar O site exhibit a dramatic decrease. We interpret these results as microscopic evidence for a spatially inhomogeneous charge distribution, where the NMR signal from O sites in the domain walls of the spin density modulation are wiped out due to large hyperfine fields, and the remaining signal arises from the intervening Mott insulating regions.
我们报告了条纹有序的La(1.8 - x)Eu0.2Sr(x)CuO4体系中的17O核磁共振(NMR)结果。在大约80 K的温度T(q)以下,平面O位的局部电场梯度和NMR信号的绝对强度显著降低。我们将这些结果解释为空间不均匀电荷分布的微观证据,其中自旋密度调制畴壁中O位的NMR信号由于大的超精细场而被消除,其余信号来自中间的莫特绝缘区域。