Collective mode in a superconductor with mixed-symmetry order parameter components

We consider a superconducting state with mixed-symmetry order parameter components, e.g., d + is or d + id' with d' = d(xy). We argue for the existence of a new orbital magnetization mode which corresponds to oscillations of relative phase phi between two components around an equilibrium value of phi = pi/2 It is similar to the clapping mode in superfluid He-3-A. we estimate the frequency of this of mode omega(0)(B, T) depending on the field and temperature for the specific case of magnetic field induced d' = d(xy) state. This mode is tunable with a magnetic field with omega(0)(B,T) proportional to B Delta(0), where Delta(0) is the magnitude of the d-wave order parameter. We also estimate the velocity s(B, T) of this mode.