  We report a proximity-driven large anomalous Hall effect in all-telluride
heterostructures consisting of ferromagnetic insulator Cr2Ge2Te6 and
topological insulator (Bi,Sb)2Te3. Despite small magnetization in the
(Bi,Sb)2Te3 layer, the anomalous Hall conductivity reaches a large value of
0.2e2/h in accord with a ferromagnetic response of the Cr2Ge2Te6. The results
show that the exchange coupling between the surface state of the topological
insulator and the proximitized Cr2Ge2Te6 layer is effective and strong enough
to open the sizable exchange gap in the surface state.
