Suppression of 2D superconductivity by the magnetic field: Quantum corrections vs. the superconductor-insulator transition

Magnetotransport of superconducting Nd2 - xCexCuO4 + y (NdCeCuO) films is studied in the temperature interval 0.3-30 K. The microscopic theory of the quantum corrections to conductivity, both in the Cooper and in the diffusion channels, qualitatively describes the main features of the experiment, including the negative magnetoresistance in the high-field limit. Comparison with the model of the field-induced superconductor-insulator transition is included and a crossover between these two theoretical approaches is discussed. (C) 2003 MAIK Nauka/Interperiodica.