Single-particle properties of a model for coexisting charge and spin quasicritical fluctuations coupled to electrons

We study the single-particle spectral properties of a model for coexisting antiferromagnetic and incommensurate charge-density-wave critical fluctuati ons coupled to electrons, which naturally arises in the context of the stri pe-quantum-critical-point scenario for high-T-c superconducting materials. Within a perturbative approach, we show that the on-shell inverse scatterin g time deviates from the normal Fermi-liquid behavior near the points of th e Fermi surface connected by the characteristic wave vectors of the critica l fluctuations (hot spots). The anomalous behavior is stronger when the hot spots are located near singular points of the electronic spectrum. The vio lations to the normal Fermi-liquid behavior are associated with the transfe r of spectral weight from the quasiparticle peak to incoherent shadow peaks , which produces an enhancement of incoherent spectral weight near the Ferm i level. We use our results to discuss recent angle-resolved photoemission spectroscopy experiments on Bi2212 near optimal doping. [S0163-1829(99)0892 3-7].