Superconductivity and normal state in-plane resistivity of electron-doped cuprates Nd-Ce-CuO: screened optical-phonon approach

We have evolved an effective two-dimensional dynamic interaction, which emb odies the screening of electrons by optical phonons and by plasmons to conf er the attributes of the pairing mechanism leading to superconductivity in layered electron-doped cuprates. The electron-doped Nd-Ce-CuO cuprate behav es as an ionic solid containing isolated CuO2 layers of electrons as carrie rs, and a model dielectric function is set up that fulfils the appropriate sum rules on the electronic and ionic polarizabilities. Following strong co upling theory, the superconducting transition temperature of optimally-dope d Nd-Ce-CuO is estimated as 28 K and the energy gap ratio is larger than th e Bardeen-Cooper-Schrieffer value. The isotope effect exponent, coherence l ength and magnetic penetration depth are also estimated. Ziman's formula of resistivity is employed for analysis and a comparison is made with the tem perature-dependent resistivity of a single crystal. The estimated phonon co ntribution together with the residual resistivity is lower than the reporte d data. The subtracted data infers a clear quadratic temperature dependence from T-c to near to room temperature. The implications of the model and it s analysis are discussed.