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Phonons and hole localization in La(1.475)Nd(0.4)Sr(0.125)CuO(4)

R. J. McQueeney·J. L. Sarrao·J. S. Gardner·M. F. Hundley·R. Osborn
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Abstract

The phonon densities-of-states of La(1.475)Nd(0.4)Sr(0.125)CuO(4) and La(1.9)Sr(0.1)CuO(4) were measured using inelastic neutron scattering. The ~70 meV phonon band which appears due to hole doping in La(1.9)Sr(0.1)CuO(4) is known to arise from strong electron-lattice coupling. This phonon band is strongly suppressed in the Nd-doped compound for which T_c is also suppressed, establishing a link between in-plane oxygen optical phonons and superconductivity. This suppression is attributed to hole localization which becomes strong near the stripe ordering condition of certain cuprates near x=1/8 and competes with superconductivity.

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R. J. McQueeney, J. L. Sarrao, J. S. Gardner, M. F. Hundley, R. Osborn. 1999-07-14. Phonons and hole localization in La(1.475)Nd(0.4)Sr(0.125)CuO(4). https://arxiv.org/abs/cond-mat/9907211

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