Coexistence of antiferromagnetic ordering and high-Tc superconductivity in electron-doped superconductor Nd2-xCexCuO4

Muon spin relaxation and magnetic susceptibility measurements were performed for the electron-doped superconductor Nd2-xCexCuO4 (NCCO) with a particular attention to the vicinity of the boundary in phase diagram between the antiferromagnetic (AF) and the superconducting phases. The obtained phase diagram clearly exhibits a competitive change in the volume fraction between the two phases around the phase boundary. a dramatic decrease of the AF phase and a sudden appearance of bulk superconductivity upon doping beyond x similar to 0.13. However, the spatial coexistence of both phases is also suggested around the boundary. In contrast to the hole-doped system, the onset of T. is approximately independent on the doping in the underdoped region of NCCO. (C) 2001 Elsevier Science B.V. All rights reserved.