Sharp optical-phonon softening near optimal doping in La2-xBaxCuO4+delta observed via inelastic x-ray scattering

Article

关键词: COPPER-OXIDE SUPERCONDUCTORS;    ANOMALOUS-DISPERSION;    ENERGY RESOLUTION;    DENSITY-WAVE;    MAGNETISM;    DYNAMICS;    STATES;    MODEL;   

DOI  :  10.1103/PhysRevB.78.140511

来源: SCIE

【 摘 要 】

We report a direct observation of a sharp Kohn-type anomaly in the doubly degenerate copper-oxygen bond-stretching phonon mode occurring at q=(0.3,0,0) in La2-xBaxCuO4+delta, with x=0.14 +/- 0.01, thanks to the high Q resolution of inelastic x-ray scattering. This anomaly is clearly seen when the inelastic signal is analyzed using a single mode but is also consistent with a two-mode hypothesis, possibly due to a splitting of the degenerate modes due to symmetry-breaking stripes. Our observation shows that the effect persists at the stripe-propagation vector in a superconducting system close to optimal doping.

【 授权许可】

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