Contribution of Oscillations of the Fermi Level to the Shubnikov–de Haas and Magneto-Intersubband Oscillations in Single HgTe Quantum Wells

Abstract

Shubnikov–de Haas oscillations and magneto-intersubband oscillations of the magnetoresistance in structures with single HgTe quantum wells with a width of 10−18 nm have been experimentally investigated. The conduction band spectrum in these arrays is split by the spin–orbit interaction. This leads to beats in the Shubnikov−de Haas oscillations and gives rise to low-frequency magneto-intersubband oscillations. The mutual positions of the antinodes of the Shubnikov−de Haas oscillations and the peaks in the magneto-intersubband oscillations are unusual: at low magnetic fields, they are opposite to theoretical predictions. The measurements in high magnetic fields, at which the relative amplitude of Shubnikov–de Haas oscillations exceeds 0.2–0.3, show a change in the mutual positions of the antinodes of the Shubnikov–de Haas oscillations and the peaks in low-frequency oscillations. Numerical calculations and additional measurements at different temperatures suggest that the observed effects are due to magnetic-field-induced oscillations of the Fermi level.