HOLE-QUASI-PARTICLE BAND NARROWING IN THE 2-DIMENSIONAL T-J MODEL

We discuss exact results for the quasiparticle bandwidth W of a single dopant-induced hole carrier in finite two-dimensional t-J-model clusters with up to 16 square lattice sites. Our results indicate a substantial band narrowing with W/t varying approximately as exp(-const×t/J) over a wide parameter range. We show that our results can be interpreted as a polaronic-carrier self-localization effect for which a simple scaling theory is developed. We also compare our results to recent analytical work. © 1990 The American Physical Society.