Molecular beam epitaxy growth of SmB6 thin films

ORAL

Abstract

Samarium hexaboride (SmB6) is a topological Kondo insulator with a gap in the conduction band formed by the hybridization of the samarium 4f and 5d bands. This gives rise to an insulating bulk and a heavy, topologically protected Dirac surface state.

The majority of previous studies of SmB6 have investigated bulk crystals. However, the synthesis of epitaxial thin films presents new opportunities to tailor the surface termination, orientation, and strain, which may alter the behavior of the topologically non-trivial surface state.

In this work we use molecular beam epitaxy to grow sub-50 nm thick films of SmB6 on (001) and (111)-oriented silicon and germanium substrates. We use ex-situ x-ray diffraction to characterize the structure of the films and the impact of the substrate material and orientation. In addition, transport measurements of the films reveal a resistance plateau below around 10 K, consistent with both bulk samples and thin films reported in the literature. This work provides a platform to study the exotic ground states in strongly correlated materials.

* This work is supported by the Air Force Office of Scientific Research's (AFOSR) Multidisciplinary University Research Initiative (MURI) through Award No. FA9550-21-1-0429

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Presenters

  • Anjolaoluwa Bamtefa

    Harvard University

Authors

  • Anjolaoluwa Bamtefa

    Harvard University

  • Jason D Hoffman

    Harvard University, Harvard

  • Sandesh S Kalantre

    Stanford Institute for Materials and Energy Sciences, Stanford University Physics Department, Stanford University

  • Molly P Andersen

    Stanford University, Department of Physics, Stanford University, Stanford, California

  • David Goldhaber-Gordon

    Stanford University, Stanford Institute for Materials and Energy Sciences, Stanford University Physics Department, Department of Physics, Stanford University, Stanford, California, Stanford Institute for Materials & Energy Sciences, Stanford University

  • Jennifer E Hoffman

    Harvard University