Publication Date:
2015-02-03
Description:
We report a first principles study on the magnetic and optical properties of Ce substituted yttrium iron garnet (Ce x Y 3−x Fe 5 O 12 ) (Ce:YIG) (x = 0.125, 0.25, 0.5, and 1.0). Using density functional theory with Hubbard-U corrections, we demonstrate that Ce 3+ -Fe 3+ (tetrahedral) charge transfer is the dominating mechanism of enhanced near infrared absorption in Ce:YIG. In particular, oxygen vacancies are found to be able to stabilize Ce 3+ from converting to Ce 4+ , at the same time reduce two neighboring Fe 3+ to Fe 2+ which occupy both the octahedral and tetrahedral sites. The formation enthalpy of Ce 4+ -Fe 2+ state is strongly dependent on the distance from the Ce ion to the oxygen vacancy, which is closely related to the local lattice distortion around the Ce ion. This result provides theoretical insight for developing high figure of merit magneto-optical materials for nonreciprocal photonic applications.
Print ISSN:
0003-6951
Electronic ISSN:
1077-3118
Topics:
Physics
