An alternative interpretation of the magnetic penetration depth data on Pr2−xCexCuO4−y and La2−xCexCuO4−y

We have revisited the magnetic penetration depth data on the electron-doped cuprates, Pr2−xCexCuO4−y and La2−xCexCuO4−y. It is proposed that the transition between nodal-gap-like and nodeless-gap-like behavior upon electron-doping [e.g., see M. Kim et al., Phys. Rev. Lett. 91 (2003) 87001] 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.