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Direct imaging of lattice strain-induced stripe phases in an optimally-doped manganite

L. Sudheendra·V. Moshnyaga·B. Damaschke·K. Samwer
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Abstract

In a manganite film without quenched disorder, we show texturing in the form of insulating and metallic stripes above and below Curie temperature (Tc), respectively, by high resolution scanning tunneling microscopy/spectroscopy (STM/STS). The formation of these stripes involves competing orbital and charge orders, and are an outcome of overlapping electron wave-functions mediated by long-range lattice strain. Contrary to popular perception, electronically homogeneous stripe phase underlines the efficacy of the lattice strain in bringing about charge density modulation and in impeding the cross-talk between the order parameters, which otherwise evolves inhomogeneously in the form of orbitally-ordered insulating and orbitally disordered metallic phases.

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L. Sudheendra, V. Moshnyaga, B. Damaschke, K. Samwer. 2006-05-30. Direct imaging of lattice strain-induced stripe phases in an optimally-doped manganite. https://doi.org/10.1103/physrevb.75.172407

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