T-J MODEL FOR TRIPLET HOLES

If a t-J model applies, conventional wisdom tells that the vacancies are singlets in the high-T(c) superconductors. Recent experiments indicate, however, that doping induces significant amounts of 3d3z2-1 holes character and this should be attached to the vacancies because of Hund's rule coupling. This motivates us to consider the motion of a triplet hole in a spin S = 1/2 background. We analyze this problem on the level of the nonretracable path approximation and we find that also for J = 0 coherent motion is possible. The triplet hole has a branched hopping history. This weakens the band singularities in a ferromagnetic background, while in an antiferromagnetic background this adds nearly an additional dimension to the effective electronic dimensionality.