Citation:
Raichle M, Reznik D, Lamago D, Heid R, Li Y, Bakr M, Ulrich C, Hinkov V, Hradil K, Lin CT, et al. Highly anisotropic anomaly in the dispersion of the copper-oxygen bond-bending phonon in superconducting YBa2Cu3O 7 from inelastic neutron scattering. Physical Review Letters. 2011;(17).