An Alternative Interpretation of the Magnetic Penetration Depth Data on   Pr(2-x)Ce(x)CuO(4-y) and La(2-x)Ce(x)CuO(4-y)
  We have revisited the magnetic penetration depth data on the electron-doped cuprates Pr(2-x)Ce(x)CuO(4-y) and La(2-x)Ce(x)CuO(4-y). It is proposed that the transition between the nodal-gap-like and nodeless-gap-like behaviors upon electron-doping [see, e.g., M. Kim et al., Phys. Rev. Lett. 91, 87001 (2003)] can be due to a scattering of the quasiparticles in the d-wave superconducting state by an incipient or weak antiferromagnetic spin-density-wave. This conjecture is supported by the inelastic neutron scattering and angle-resolved photoemission experiments on some closely related electron-doped cuprates. 
Khee-Kyun Voo, Wen Chin Wu