2017/06/28 by Matteo Ippoliti, Scott Geraedts, Scott D. Geraedts +1 · 15 citations
Physics and Astronomy · #Anisotropy #Composite fermion #Condensed matter physics #Electron #Fermi Gamma-ray Space Telescope #Fermi gas #Fermi liquid theory #Fermion #Landau quantization #Physics #Physics of Superconductivity and Magnetism #Quantum Hall effect #Quantum and electron transport phenomena #Quantum mechanics #Quantum oscillations #Quantum spin Hall effect #Topological Materials and Phenomena #cond-mat.mes-hall #cond-mat.str-el #quant-ph
paper · pdf · doi:10.1103/physrevb.96.115151
published in Physical review. B./Physical review. B 96(11) (American Physical Society) · 6 pages + bibliography, 5 figures
arxiv created 2017/06/28 · openalex publication_date 2017/09/25 · arxiv updated 2017/10/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the effect of band anisotropy with discrete rotational symmetry CN (where N\ensuremath≥2) in the quantum Hall regime of two-dimensional electron systems. We focus on the composite Fermi liquid (CFL) at half-filling of the lowest Landau level. We find that the magnitude of anisotropy transferred to the composite fermions decreases very rapidly with N. We demonstrate this by performing density matrix normalization group calculations on the CFL, and comparing the anisotropy of the composite fermion Fermi contour with that of the (noninteracting) electron Fermi contour at zero magnetic field. We also show that the effective interaction between the electrons after projecting into a single Landau level is much less anisotropic than the band, a fact which does not depend on filling and thus has implications for other quantum Hall states as well. Our results confirm experimental observations on anisotropic bands with warped Fermi contours, where the only detectable effect on the composite Fermi contour is an elliptical distortion (N=2).