Demagnetization, which is inherently present in the magnetic response of small finite-size superconductors, can be approximately accounted for by an effective κ within a two-dimensional lowest Landau level approximation of the Ginzburg-Landau functional. We show this by comparing the equilibrium magnetization of superconducting mesoscopic disks obtained from the numerical solution of the three-dimensional Ginzburg-Landau equations with that obtained in the “effective” lowest Landau level approximation.

• Received 16 November 2000

DOI:https://doi.org/10.1103/PhysRevB.64.134514