2006/11/02 by Ying Ran, Ran, Ying, Xiao-Gang Wen +1 · 1 citation
Engineering · Physics and Astronomy · #Physics of Superconductivity and Magnetism #Rare-earth and actinide compounds #Superconducting Materials and Applications #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/0611034
19 pages, 18 figures
arxiv created 2006/11/02 · arxiv updated 2009/12/01
We studied underdoped high Tc superconductors using a spinon-dopon approach (or doped-carrier approach) to t-t'-t''-J model, where spinon carries spin and dopon carries both spin and charge. In this approach, the mixing of spinon and dopon describes superconductivity. We found that a nonuniform mixing in k-space is most effective in lowering the t' and t'' hopping energy. We showed that at mean-field level, the mixing is proportional to quasiparticle spectral weight Z-. We also found a simple monte-carlo algorithm to calculate Z- from the projected spinon-dopon wavefunction, which confirms the mean-field result. Thus the non-uniform mixing caused by t' and t" explains the different electron spectral weights near the nodal and anti-nodal points (\it i.e. the dichotomy) observed in underdoped high Tc superconductors. For hole-doped sample, we found that Z is enhanced in the nodal region and suppressed in the anti-nodal region. For electron doped sample, the same approach leads to a suppressed Z in the nodal region and enhanced in the anti-nodal region, in agreement with experimental observations.