Density of states measurements for heavy subband of holes in HgTe quantum wells
arXiv:1907.07731 · doi:10.1103/PhysRevB.101.085301
Abstract
Valence band in narrow HgTe quantum wells contains well-conductive Dirac-like light holes at the point and poorly conductive heavy hole subband located in the local valleys. Here we propose and employ two methods to measure the density of states for these heavy holes. The first method uses a gate-recharging technique to measure thermodynamical entropy per particle. As the Fermi level is tuned with gate voltage from light to heavy subband, the entropy increases dramatically, and the value of this increase gives an estimate for the density of states. The second method determines the density of states for heavy holes indirectly from the gate voltage dependence of the period of the Shubnikov-de Haas oscillations for light holes. The results obtained by both methods are in the reasonable agreement with each other. Our approaches can be applied to measure large effective carrier masses in other two-dimensional gated systems.
arXiv comment9 pages, 5 figures
References in corpus (30)
- Quantum Spin Hall Insulator State in HgTe Quantum Wells
- Room-Temperature Quantum Hall Effect in Graphene
- Observation of the chiral anomaly induced negative magneto-resistance in 3D Weyl semi-metal TaAs
- Observation of Dirac Holes and Electrons in a Topological Insulator
- Band structure of semimagnetic Hg1-yMnyTe quantum wells
- Large nonsaturating magnetoresistance and signature of non-degenerate Dirac nodes in ZrSiS
- Single valley Dirac fermions in zero-gap HgTe quantum wells
- The low-density spin susceptibility and effective mass of mobile electrons in Si inversion layers
- Transport properties of a 3D topological insulator based on a strained high mobility HgTe film
- Pressure and temperature driven phase transitions in HgTe quantum wells
- Split Dirac cones in HgTe/CdTe quantum wells due to symmetry-enforced level anticrossing at interfaces
- Temperature-induced topological phase transition in HgTe quantum wells
- Strongly correlated two-dimensional plasma explored from entropy measurements
- Spin-Droplet State of an Interacting 2D Electron System
- Spin-orbit splitting of valence and conduction bands in HgTe quantum wells near the Dirac point
- Two-dimensional semimetal in a wide HgTe quantum well: magnetotransport and energy spectrum
- The valence band energy spectrum of HgTe quantum wells with inverted band structures
- Full Momentum and Energy Resolved Spectral Function of a 2D Electronic System
- Direct measurements of the fractional quantum Hall effect gaps
- Thermodynamic magnetization of two-dimensional electron gas measured over wide range of densities
- Low temperature Hall effect in bismuth chalcogenides thin films
- Quantization of entropy in a quasi-two-dimensional electron gas
- Entropy spikes as a signature of Lifshitz transitions in the Dirac materials
- Detection of topological phase transitions through entropy measurements: the case of germanene
- Hole transport and valence band dispersion law in a HgTe quantum well with normal energy spectrum
- Effective Mass and Spin Susceptibility of Dilute Two-Dimensional Holes in GaAs
- Simple mechanisms that impede the Berry phase identification from magneto-oscillations
- Gate-tunable Electronic Transport in p-type GaSb Quantum Wells
- Quantum capacitance of an HgTe quantum well as an indicator of the topological phase
- Temperature derivative of the chemical potential and its magnetooscillations in two-dimensional system