Anisotropically damped magnetic excitations in La_2-xSr_xCuO₄

The collective magnetic excitations in cuprate materials have been the subject of significant research to unravel their potential role in the superconducting pairing mechanism [1]. We have performed resonant inelastic x-ray scattering (RIXS) measurements on these excitations on the model cuprate superconductor La2-xSrxCuO4 with doping x=0, x=0.12 and x=0.16. We find that the line-shape of the excitations is fairly-well described by a damped harmonic oscillator response model [2]. The damping parameter is strongly q-dependent. We perform measurements along high symmetry directions and, for the doped compounds, extend beyond this to map a full portion of the Brillouin zone revealing the anisotropy of the damping of excitation. The results are compared with high-energy inelastic neutron scattering.

References

1. Scalapino, D. J Rev. Mod. Phys. 84 1383 (2012)
2. Monney, C. et al. Phys. Rev. B 93 075103 (2016)