we introduce a new perspective on magnetoplasmonics in nickel nanoferromagnets by exploiting the phase tunability of the optical polarizability due to localized surface plasmons and simultaneous magneto - optical activity . 
 we demonstrate how the concerted action of nanoplasmonics and magnetization can manipulate the sign of rotation of the reflected light s polarization ( i.e. , to produce kerr rotation reversal ) in ferromagnetic nanomaterials and , further , how this effect can be dynamically controlled and employed to devise conceptually new schemes for biochemosensing .