Collective spin-orbit waves in theBphase ofHe3

Abstract
The collective modes associated with oscillations of the order parameter in the B phase are calculated. The phase is assumed to be the Balian-Werthamer state, and it is shown that there are three collective modes in which both the orbital and spin angular momenta of the Cooper pairs oscillate. The two modes with transverse polarization are found to have a velocity 2 times as large as the longitudinal mode. In the presence of the dipole interaction these modes are mixed, with one mode becoming the longitudinal resonance in zero field.