Modulated microwave absorption of Nd_2-xCe_xCuO₄ single crystals

Modulated microwave absorption shows that as-grown crystals of Nd2-xCexCuO4 already contain superconducting regions prior to reduction, which then increases the measured Tc from 7 to 21 K. The temperature dependence of the modulated absorption has a maximum near Tc, indicating the reduced role of weak Josephson junctions in these crystals compared to ceramic samples of the cuprate superconductors. © 1990.