Conversion from transparent antiferromagnet KNi F3 to transparent ferrimagnets

Abstract

We succeeded in performing a magnetic conversion from transparent antiferromagnet KNi F3 to transparent ferrimagnets, with a spontaneous ferromagnetic moment by a percolation method. Considering Coulomb repulsion, the origin of the spontaneous ferromagnetic moment is explained by an inhomogeneous antiferromagnetic spin arrangement, even if nonmagnetic ions are dispersed homogenously over KNi F3. The ferromagnetic transition temperature was obtained to be 24-26 K. The transmittance at 600-1000 nm was excellent. This compound shows an alternative that can be used for an optical isolator that uses commercial semiconductor lasers, and can widely be used in next generation optical information networks. © 2008 American Institute of Physics.