2015/12/31 by Shengjun Yuan, Edo van Veen, M. I. Katsnelson +2 · 2 citations
Materials Science · Mathematics · Physics and Astronomy · #2D Materials and Applications #Band gap #Condensed matter physics #Graphene research and applications #Landau quantization #Magnetic field #Mathematics #Physics #Quantization (signal processing) #Quantum Hall effect #Quantum mechanics #Quantum spin Hall effect #Semimetal #Topological Materials and Phenomena #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.93.245433
published as Phys. Rev. B 93, 245433 (2016) · 8 pages, 7 figures
arxiv created 2016/06/28 · openalex publication_date 2016/06/28 · arxiv updated 2016/06/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the quantum Hall effect of two-dimensional electron gas in black phosphorus in the presence of perpendicular electric and magnetic fields. In the absence of a bias voltage, the external magnetic field leads to a quantization of the energy spectrum into equidistant Landau levels, with different cyclotron frequencies for the electron and hole bands. The applied voltage reduces the band gap, and eventually a semiconductor-to-semimetal transition takes place. This nontrivial phase is characterized by the emergence of a pair of Dirac points in the spectrum. As a consequence, the Landau levels are not equidistant anymore but follow the \ensuremathεn\ensuremath∝√(nB) characteristic of Dirac crystals as graphene. By using the Kubo-Bastin formula in the context of the kernel polynomial method, we compute the Hall conductivity of the system. We obtain a \ensuremathσxy\ensuremath∝2n quantization of the Hall conductivity in the gapped phase (standard quantum Hall effect regime) and a \ensuremathσxy\ensuremath∝4(n+1/2) quantization in the semimetallic phase, characteristic of Dirac systems with nontrivial topology.