SPIN-WAVE FREQUENCY-SHIFTS IN EXCHANGE-COUPLED FERROMAGNET ANTIFERROMAGNET STRUCTURES - APPLICATION TO CO/COO/

Co/CoO structures have been studied almost exclusively through measure ments of hysteresis, and display an enhanced and strongly temperature dependent effective in-plane anisotropy. A recent experimental study d emonstrated an alternate way of investigating effects related to the c oupling across the interface by measuring frequencies of long waveleng th spin waves associated with the Co film, A large increase in frequen cy of the low frequency spin wave in the Co was observed as the temper ature was lowered through the Neel temperature of CoO. We show how the se frequency shifts can be understood as an effective interface anisot ropy introduced by strong exchange coupling across the Co/CoO interfac e. This means that spin waves in the Co also include energy contributi ons from the larger anisotropies experienced by spins in the CoO. The theory is presented and discussed for the Co/CoO interface and other s tructures. (C) 1997 American Institute of Physics.