HYBRID WAVES IN MAGNETOSTRICTIVE FERROMAGNETICS

Interaction between acoustic field and electromagnetic field, in a mag netostrictive ferromagnetic material produces both transversal quasiac oustic waves (QACW) and quasielectromagnetic waves (QEMW) named hybrid waves. Properties of hybrid waves have been studied and their depende nce on conductivity has been emphasized in the piezomagnetic case. To this end, the system of Maxwell's equations, Newton's law of force, an d piezomagnetic state equations were solved for an infinite continuous medium. It is shown that for a particular conductivity value sigma(c) , the hybrid modes coincides in a mixed propagation mode we called MHW M. The dispersion relation, in the case of separate hybrid waves, as w ell as in the mixed mode MHWM, is discussed. The MHWM has a velocity V (c), which is independent of wave number k. Moreover we point out that (a) for very high sigma, the QEMW velocity reaches a k-independent va lue while the QACW velocity falls to zero, (b) the behavior of sigma(c )(k), at constant V(c), is linear, (c) for sigma not-equal sigma(c), a t constant sigma, the QEMW velocity and QACW velocity behaviors versus k are nonmonotonics.