We demonstrate the van der Waals epitaxy of the topological insulator
compound Bi2Te3 on the ferromagnetic insulator Cr2Ge2Te6. The layers are
oriented with (001) of Bi2Te3 parallel to (001) of Cr2Ge2Te6 and (110) of
Bi2Te3 parallel to (100) of Cr2Ge2Te6. Cross-sectional transmission electron
microscopy indicates the formation of a sharp interface. At low temperatures,
bilayers consisting of Bi2Te3 on Cr2Ge2Te6 exhibit a large anomalous Hall
effect (AHE). Tilted field studies of the AHE indicate that the easy axis lies
along the c-axis of the heterostructure, consistent with magnetization
measurements in bulk Cr2Ge2Te6. The 61 K Curie temperature of Cr2Ge2Te6 and the
use of near-stoichiometric materials may lead to the development of spintronic
devices based on the AHE.Comment: Related papers at http://pettagroup.princeton.ed
