Epitaxial growth of Bi$_2$Te$_3$ on the Ferromagnetic Insulator Cr$_2$Ge$_2$Te$_6$

ORAL

Abstract

We report the experimental realization of a new topological insulator-ferromagnetic insulator (TI-FI) material system: the Cr$_2$Ge$_2$Te$_6$-Bi$_2$Te$_3$ heterostructure. The layered chalcogenide FI Cr$_2$Ge$_2$Te$_6$ exhibits a high Curie temperature of 61 K and a resistivity greater than $10^3$ $\Omega$-cm below 77 K, which suit it well for the study of magnetic proximity effects in TI-FI heterostructures. We fabricate heterostructures by growing single crystalline Cr$_2$Ge$_2$Te$_6$ substrates and depositing Bi$_2$Te$_3$ thin films using metalorganic chemical vapor deposition. Cross-sectional transmission electron microscopy reveals a sharp interface along the (0 0 1) planes of the two crystals, with the structures uniformly oriented as Cr$_2$Ge$_2$Te$_6$[1$\bar 1$0]//Bi$_2$Te$_3$[0$\bar 1$0]. The coupling between the Cr$_2$Ge$_2$Te$_6$ and Bi$_2$Te$_3$ layers is studied via the anomalous hall effect.

*We are grateful for support from the NSF funded Princeton MRSEC (DMR-0819860)

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Authors

  • L.D. Alegria

    • Princeton University Physics Department

  • Huiwen Ji

    • Princeton University Chemistry Department
    • Department of Chemistry, Princeton University

  • N. Yao

    • Princeton Institute for the Science and Technology of Materials

  • Robert Cava

    • Department of Chemistry, Princeton University
    • Department of Chemistry, Princeton university, Princeton NJ 08544 USA
    • Princeton University Chemistry Department
    • Institute for Quantum Matter, Princeton University
    • Department of Chemistry, Princeton University, NJ, 08544, USA
    • Princeton University

  • J.R. Petta

    • Princeton University
    • Princeton University Physics Department
    • Department of Physics, Princeton University