2016/03/31 by T. Kernreiter, Michele Governale, M. Governale +1
Materials Science · Mathematics · Physics and Astronomy · #2D Materials and Applications #Capacitance #Condensed matter physics #Electron #Graphene research and applications #Heterojunction #Mathematics #Observable #Physics #Quantum #Quantum capacitance #Quantum mechanics #Quantum well #Topological Materials and Phenomena #Topological insulator #Topology (electrical circuits) #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.93.241304
published as Phys. Rev. B 93, 241304 (2016) · 6 pages, 7 figures, v2: minor changes, version to appear as Rapid Communication in Phys. Rev. B
arxiv created 2016/06/02 · openalex publication_date 2016/06/15 · arxiv updated 2016/06/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Varying the quantum-well width in an HgTe/CdTe heterostructure allows for realizing normal and inverted semiconducting band structures, making it a prototypical system to study two-dimensional (2D) topological-insulator behavior. We have calculated the zero-temperature thermodynamic density of states DT for the electron-doped situation in both regimes, treating interactions within the Hartree-Fock approximation. A distinctively different behavior for the density dependence of DT is revealed in the inverted and normal cases, making it possible to detect the system's topological phase through measurement of macroscopic observables, such as the quantum capacitance or electronic compressibility. Our results establish the 2D electron system in HgTe quantum wells as unique in terms of its collective electronic properties.