Jorge Quintanilla and Orion Ciftja, Scientific Reports 13, 1400 (2023). https://doi.org/10.1038/s41598-023-28614-z
We present a theory of spontaneous Fermi surface deformations for half‑filled Landau levels (filling factors of the form ν = 2 n + 1/2). We assume the half‑filled level to be in a compressible, Fermi liquid state with a circular Fermi surface. The Landau level projection is incorporated via a modified effective electron‑electron interaction and the resulting band structure is described within the Hartree‑Fock
approximation. We regulate the infrared divergences in the theory and probe the intrinsic tendency of the Fermi surface to deform through Pomeranchuk instabilities. We find that the corresponding susceptibility never diverges, though the system is asymptotically unstable in the n → ∞ limit.