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arXiv · 1812.02468

Massless Dirac fermions in III-V semiconductor quantum wells

S. S. Krishtopenko·W. Desrat·K. E. Spirin·C. Consejo·S. Ruffenach·F. Gonzalez-Posada·B. Jouault·W. Knap·K. V. Maremyanin·V. I. Gavrilenko·G. Boissier·J. Torres·M. Zaknoune·E. Tournié·F. Teppe
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Abstract

We report on the clear evidence of massless Dirac fermions in two-dimensional system based on III-V semiconductors. Using a gated Hall bar made on a three-layer InAs/GaSb/InAs quantum well, we restore the Landau levels fan chart by magnetotransport and unequivocally demonstrate a gapless state in our sample. Measurements of cyclotron resonance at different electron concentrations directly indicate a linear band crossing at the $\Gamma$ point of Brillouin zone. Analysis of experimental data within analytical Dirac-like Hamiltonian allows us not only determing velocity $v_F=1.8\cdot10^5$ m/s of massless Dirac fermions but also demonstrating significant non-linear dispersion at high energies.

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S. S. Krishtopenko, W. Desrat, K. E. Spirin, C. Consejo, S. Ruffenach, F. Gonzalez-Posada, B. Jouault, W. Knap, K. V. Maremyanin, V. I. Gavrilenko, G. Boissier, J. Torres, M. Zaknoune, E. Tournié, F. Teppe. 2018-12-06. Massless Dirac fermions in III-V semiconductor quantum wells. https://doi.org/10.1103/physrevb.99.121405

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