Magnetic proximity-induced anomalous Hall effect in magnetic topological insulator trilayers Cr₂Ge₂Te₆/(Bi,Sb)₂Te₃/Eu₃Fe₅O₁₂

Heterostructures composed of topological insulators (TIs) and magnetic materials have garnered significant interest due to the novel phenomena emerging from the interfaces and their potential applications in spintronics. Among these, trilayer magnetic TI heterostructures, which utilize magnetic insulators with high Curie temperatures and different coercivities, hold great promise for realizing quantum anomalous Hall or axion insulator state with less disorder. In this work, we investigate the thin film growth and the electrical transport of Cr₂Ge₂Te₆ (CGT)/(Bi_1-xSb_x)₂Te₃ (BST)/Eu₃Fe₅O₁₂ (EuIG). We successfully fabricated high-quality epitaxial films by sputtering for EuIG and molecular beam epitaxy for BST and CGT, with clean interfaces through ultra-high vacuum sample transfer. By tuning BST compositions in 12 nm CGT/7 nm BST/20 nm EuIG, the anomalous Hall resistance and sheet resistance increased as the carrier density decreased, with all Hall polarities remaining positive. The largest magnetic proximity-induced anomalous Hall resistance reached 250 Ω at 2 K. Additionally, we observed hysteretic butterfly-shaped magnetoresistance, where the low-field behavior changed from positive, indicating weak anti-localization, to negative, signifying weak localization, as the composition and carrier type transitioned from Bi-rich n-type to Sb-rich p-type. Ongoing studies focus on the thickness dependence of BST as well as the CGT, and the results will be presented in this work.