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Microscopic Charge Inhomogeneities in Underdoped La_2-xSr_xCuO_4: Local Structural Evidence

S. J. L. Billinge·E. S. Bozin·M. Gutmann·H. Takagi
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Abstract

We present local structural evidence for the existence of charge inhomogeneities at low temperature in underdoped and optimally doped La_2-xSr_xCuO_4. The inhomogeneities disappear for x > 0.2. The evidence for the charge inhomogeneities comes from an anomalous increase in the in-plane Cu-O bond length distribution in the underdoped samples as well as evidence for CuO_6 octahedral tilt inhomogeneities in the intermediate range structure. Preliminary analysis of the temperature dependence of this phenomenon indicates that the inhomogeneities set in at temperatures in the range 60 K < Tco < 130 K which depends on doping.

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S. J. L. Billinge, E. S. Bozin, M. Gutmann, H. Takagi. 2000-05-02. Microscopic Charge Inhomogeneities in Underdoped La_2-xSr_xCuO_4: Local Structural Evidence. https://arxiv.org/abs/cond-mat/0005032

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