CHERN-SIMONS SUPERCONDUCTIVITY AT FINITE MAGNETIC-FIELD

We study Chem-Simons (CS) superconductivity in the presence of uniform external magnetic field of arbitrary strength for a system of fermion s in two spatial dimensions, which are minimally coupled both to the C S and Maxwell gauge fields. We have carried out the computation within the mean-field ansatz. Analyzing only the mean field (i.e., ignoring the fluctuations of the gauge fields), we find that chemical potential , susceptibility, and magnetization show discontinuities for integer n umber of filled Landau levels. Taking into account the fluctuations of the gauge fields, we find that the masses of the excitations increase with the magnetic field, and that the presence of nonlinear magnetic susceptibilities shows the absence of any critical or pseudocritical m agnetic field. Finally, an interesting result is that, unlike ordinary superconductors, the system is magnetically asymmetric.