Microscopic Charge Inhomogeneities in Underdoped La₂-xSrₓCuO₄: Local Structural Evidence

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We present local structural evidence for the existence of charge inhomogeneities at low temperature in underdoped and optimally doped La₂-xSrₓCuO₄. 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 CuO₆ 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.