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arXiv · 1802.09494

Two-Dimensional Dirac Fermions in Thin Films of Cd3As2

Luca Galletti·Timo Schumann·Omor F. Shoron·Manik Goyal·David A. Kealhofer·Honggyu Kim·Susanne Stemmer
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Abstract

Two-dimensional states in confined thin films of the three-dimensional Dirac semimetal Cd3As2 are probed by transport and capacitance measurements under applied magnetic and electric fields. The results establish the two-dimensional Dirac electronic spectrum of these states. We observe signatures of p-type conduction in the two-dimensional states as the Fermi level is tuned across their charge neutrality point and the presence of a zero energy Landau level, all of which indicate topologically non-trivial states. The resistance at the charge neutrality point is approximately h/e2 and increases rapidly under the application of a magnetic field. The results open many possibilities for gate-tunable topological devices and for the exploration of novel physics in the zero energy Landau level.

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Luca Galletti, Timo Schumann, Omor F. Shoron, Manik Goyal, David A. Kealhofer, Honggyu Kim, Susanne Stemmer. 2018-02-26. Two-Dimensional Dirac Fermions in Thin Films of Cd3As2. https://doi.org/10.1103/physrevb.97.115132

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