Giant Electron-Phonon Anomaly in Doped La₂CuO₄and Other Cuprates

Figure 14

Bond-stretching phonon dispersion (top row) and linewidth (bottom row) at three doping levels. Black lines represent downward cosine dispersion. The overall increase in the linewidth of the bond-stretching mode towards the zone boundary appears to be doping-independent. Softening compared with the cosine dispersion as well as the linewidth enhancement half-way to the zone boundary do not shift with h between x = 0.07 and 0.15 [44].

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