2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/221672We discuss properties of the two-dimensional Landau Hamiltonian perturbed by a family of identical $δ$ potentials arranged equidistantly along a closed loop. It is demonstrated that for the loop size exceeding the effective size of the point obstacles and the cyclotronic radius such a system exhibits persistent currents at the bottom of the spectrum. We also show that the effect is sensitive to a small disorder.13 pages 14 figuresQuantum PhysicsMesoscale and Nanoscale Physicstext