Dysprosium substituted Ce:YIG thin films with perpendicular magnetic anisotropy for silicon integrated optical isolator applications

Abstract

In this report, dysprosium substituted Ce[subscript 1]Y[subscript 2]Fe[subscript 5]O[subscript 12] (Ce:YIG) thin films (Dy:CeYIG) with perpendicular magnetic anisotropy (PMA) are successfully deposited on silicon and silicon-on-insulator waveguides by pulsed laser deposition. The structural, magnetic, and magneto-optical properties of Dy:CeYIG films are investigated. We find that increasing dysprosium concentration leads to a decreased out-of-plane magnetic saturation field. Dy[subscript 2]Ce[subscript 1]Fe[subscript 5]O[subscript 12] and Dy[subscript 2]Ce[subscript 1]Al[subscript 0.4]Fe[subscript 4.6]O[subscript 12] thin films show PMA dominated by magnetoelastic effects due to thermal mismatch strain. These films further exhibit high Faraday rotation and low optical loss. Our work demonstrates that Dy substitution is an effective way to induce PMA in Ce:YIG thin films without compromising their magneto-optical figure of merit, making this material promising for self-biased transverse electric mode optical isolator applications.