Capacitance spectroscopy of a system of gapless Dirac fermions in a HgTe quantum well

作者: D. A. Kozlov , M. L. Savchenko , J. Ziegler , Z. D. Kvon , N. N. Mikhailov

DOI: 10.1134/S0021364016240103

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摘要: Information on the density of states two-dimensional Dirac fermions in a 6.6-nm-thick HgTe quantum well that corresponds to transition from direct inverted spectrum is obtained for first time by means capacitance measurements. It found electrons linear function Fermi energy at EF > 30 meV with corresponding velocity vDF = 8.2 × 105 m/s. At lower energies, this dependence deviates law, indicating strong effect disorder, which associated fluctuations built-in charge, studied system near point. negative sharp increase observed, tail valleys heavy holes. The described behavior agreement proposed model, includes both features real and fluctuation potential.

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