We succesfully combined two topological insulators, namely  Bi₂Te₃ and Sb₂Te₃ with a full in situ metal organic chemical vapor deposition (MOCVD) on top of large area (4″) Si(111) substrates. The bottom Sb₂Te₃ layer serves as an ideal seed layer for the growth of highly crystalline Bi₂Te₃ on top, also inducing a remarkable shift of the Fermi level to place it very close to the Dirac point, as visualized by angle-resolved photoemission spectroscopy. Such ideal topologically-protected surface states are exploited in the simple spin-charge converter Si(111)/Sb₂Te₃/Bi₂Te₃/Au/Co/Au, where by by spin pumping ferromagnetic resonance we measure a large spin-charge conversion at room temperature, which is highly interesting in view of the future technology transfer of these materials for spintronics.

The research is published open acccess at ACS Appl. Mater. Interfaces (2023). 

For any enquireies please contact Dr. Roberto Mantovan