title: Marginal Fermi liquid resonance induced by a quantum magnetic impurity in d-wave superconductors.
abstract: We consider a model of an Anderson impurity embedded in a d(x(2)-y(2))--wave superconducting state to describe the low-energy excitations of cuprate superconductors doped with a small amount of magnetic impurities. Because of the Dirac-like energy dispersion, a sharp localized resonance above the Fermi energy, showing a marginal Fermi liquid behavior ( omega ln omega as omega-->0), is predicted for the impurity states. The same logarithmic dependence of self-energy and a linear frequency dependence of the relaxation rate are also derived for the conduction electrons, characterizing a new universality class for the strong coupling fixed point. At the resonant energies, the spatial distribution of the electron density of states around the magnetic impurity is also calculated.
authors.affiliation: Center for Advanced Studies, Tsinghua University, Beijing, China.
authors.forename: G M
authors.initials: GM
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Hu
authors.forename: L
authors.initials: L
authors.lastname: Yu