  A spin-1 ferromagnetic Bose-Einstein condensate subject to a certain magnetic
field exhibits a broken-axisymmetry phase in which the magnetization tilts
against the applied magnetic field due to the competition between
ferromagnetism and linear and quadratic Zeeman effects. The Bogoliubov analysis
shows that in this phase two Goldstone modes associated with U(1) and SO(2)
symmetry breakings exist, in which phonons and magnons are coupled to restore
the two broken symmetries.
