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NMR Evidence for Charge Inhomogeneity in Stripe Ordered La_{1.8-x}Eu_{0.2}Sr_{x}CuO_4

H. -J. Grafe·N. J. Curro·M. Hücker·B. Büchner
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Abstract

We report ^{17}O Nuclear Magnetic Resonance (NMR) results in the stripe ordered La_{1.8-x}Eu_{0.2}Sr_{x}CuO_4 system. Below a temperature T_q ~ 80K, the local electric field gradient (EFG) 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.

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H. -J. Grafe, N. J. Curro, M. Hücker, B. Büchner. 2005-11-16. NMR Evidence for Charge Inhomogeneity in Stripe Ordered La_{1.8-x}Eu_{0.2}Sr_{x}CuO_4. https://doi.org/10.1103/physrevlett.96.017002

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