Doped Mott insulators and single-particle spectroscopies

Mohit Randeria

Department of Physics, Ohio State University, 174 W 18th Avenue, Columbus, Ohio 43210, USA

We use a variational approach and exact sum rules to gain insight into doped Mott insulators, especially the strongly correlated d-wave superconducting state of the high Tc superconductors. In this talk I will focus on results which have direct relevance to ARPES and STM experiments. To begin with I will describe results for the doping dependence of the gap and contrast it with that for the SC order parameter. I will then discuss theoretical results on the coherent spectral weight and dispersion of nodal quasiparticles. Finally I will describe results on the sum rules for one-particle spectroscopies, which shed light on the striking asymmetry in the tunneling spectra of high Tc superconductors and should also be useful in estimating the local doping variations in inhomogeneous materials.