We investigate by resonant inelastic x-ray scattering the magnetic excitations in thin films of tetragonal CuO. We identify a spin wave excitation, dispersing on two cupratelike antiferromagnetic sublattices. Its energy at the boundary of the Brillouin zone (220 meV), is significantly lower than typical values (E ∼300 meV) found in two-dimensional cuprates. A spin wave expansion starting from an extended Hubbard model suggests two possible scenarios for this energy lowering.
|Number of pages||5|
|Journal||Physical review B: Condensed matter and materials physics|
|Publication status||Published - 6 Oct 2015|