Signature of Spin Collective Mode in Local Tunneling Spectra of a d-wave   Superconductor
  We consider the influence of magnetic excitations on the local density of states in the d-wave superconductor. The magnetic susceptibility is calculated within the renormalized $t-t'-J$ model and its influence on the quasiparticle self-energy is considered using a minimal model originally proposed by Polkovnikov {\it et al.}[cond-mat/0203176]. We find the local density of states possess periodic components both along $(\pi,0)$ and $(\pi,\pi)$ directions with the associated wavevectors changing in magnitude as the quasiparticle energy is varied. Comparison with the STM experiment reveals that the calculated LDOS modulation is inconsistent with the measured data. 
Jung Hoon Han (Konkuk University)