Giant Electron-Phonon Anomaly in Doped La₂CuO₄and Other Cuprates

Figure 4

Calculated (lines) and observed (filled dots) phonon frequencies in YNi₂B₂C at 20 K. Open dots along [100] were measured at 300 K. Branches shown in red/black refer to phonons of predominantly longitudinal/transverse polarization respectively. The horizontal axes denote different crystallographic directions in reciprocal lattice units (r.l.u.). The theoretical results were scaled up by a factor of 1.03 (from [18]).