Evolution of Hole and Spin Dynamics in High Temperature Superconductors   within the Small Hole Density Limit of the t-J Model
  The evolution of hole and spin dynamics in high temperature superconductors is studied within the self-consistent noncrossing approximation of the t-J model in the small hole density limit. As the doping concentration is increased, long-range electron correlations disappear rapidly and the quasiparticle energy band becomes considerably narrow. At a small hole density long-range antiferromagnetic order is destroyed leading to the inadequacy of spin wave basis approximation near small wave vectors. Spin excitations near the antiferromagnetic zone boundary are strongly renormalized and damped but they are still well described within spin wave basis approximation. 
Bumsoo Kyung (Max Planck Institute)