Difference between the cleaved surface and the polished surface on the Raman spectra of La$_{2-x}$Sr$_x$CuO$_4$

S. Sugai; Y. Takayanagi; N. Hayamizu

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Difference between the cleaved surface and the polished surface on the Raman spectra of La$_{2-x}$Sr$_x$CuO$_4$

S. Sugai·Y. Takayanagi·N. Hayamizu

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Abstract

The Raman spectra on the cleaved surface of La$_{2-x}$Sr$_x$CuO$_4$ is found to be different from those on the mechanically polished or chemically etched surface. On the cleaved surface, the step-like increase of the scattering intensity below 700 cm$^{-1}$ is washed away and the two-phonon peaks are preserved clearly even at the optimum doping. The difference is demonstrated on the optimally doped crystal at x=0.15 and the stripe phase crystal at x=0.115. The stripe phase is stabilized by defects induced by mechanical polishing.

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S. Sugai, Y. Takayanagi, N. Hayamizu. 2000-10-12. Difference between the cleaved surface and the polished surface on the Raman spectra of La$_{2-x}$Sr$_x$CuO$_4$. https://arxiv.org/abs/cond-mat/0010174

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