Connecting spin and charge response in electron-doped cuprates

We perform a detailed analysis of angle-resolved photoemission data from electron-doped cuprates [1,2] in order to extract both the self-energy and the bare dispersion of the quasiparticles. The self-energy contains important information about the interactions among the quasiparticles. Taking the extracted bare quasiparticle dispersion as an input parameter we compute dynamical response functions employing a spin-fluctuation-based theory. In particular we estimate the dynamical spin susceptibility, which we then compare to recent inelastic neutron scattering data [3]. We obtain a resonance at the anti-ferromagnetic ordering wavevector $(\pi, \pi)$, whereas incommensurate spin excitations are mostly suppressed. Our approach provides a consistent theoretical description of both the spin and charge response in electron-doped cuprates. \newline \newline [1] H.~Matsui \textit{et al.}, Phys.~Rev.~Lett. \textbf{94}, 047005 (2005). \newline [2] H.~Matsui and T.~Takahashi, private communication. \newline [3] S.~D.~Wilson \textit{et al.}, Phys.~Rev.~B \textbf{74}, 144514 (2006).