Effects of the applied magnetic field and anisotropy on the spin wave gap in ultrathin magnetic films at zero temperature

We investigate the calculated spin wave gap of two-dimensional magnetic films under the combined influence of the in-plane direction of the applied magnetic field and different kinds of magnetic anisotropies. We also compute the spin wave gap as a function of the applied magnetic field at zero temperature. We discuss the results in connection with experimental data reported for epitaxial Fe-deficient yttrium garnet (YIG) films grown by pulsed laser deposition (PLD) technique onto the different faces of the Gd3Ga5O12 single crystal.