Using as a model the Hubbard Hamiltonian we determine various basic properties of electron-doped cuprate superconductors like ${ Nd}_{ 2-x}{ Ce}_{ x}{ CuO}_{ 4}$ and ${ Pr}_{ 2-x}{ Ce}_{ x}{ CuO}_{ 4}$ for a spin-fluctuation-induced pairing mechanism. Most importantly we find a narrow range of superconductivity and like for hole-doped cuprates $d_{ x^{ 2}-y^{ 2}}$ - symmetry for the superconducting order parameter. The superconducting transition temperatures $T_{ c}(x)$ for various electron doping concentrations $x$ are calculated to be much smaller than for hole-doped cuprates due to the different Fermi surface and a flat band well below the Fermi level. Lattice disorder may sensitively distort the symmetry $d_{ x^{ 2}-y^{ 2}}$ via electron-phonon interaction.
Categories: cond-mat.supr-con cond-mat.str-el