Signatures of a staggered-flux phase in the t-J model with two holes on   a 32-site lattice
  We study the relevance of the staggered-flux phase in the t-J model using a system with two holes on a 32-site lattice with periodic boundary conditions. We find a staggered-flux pattern in the current-current correlation in the lowest energy d-wave state where there is mutual attraction between the holes. This staggered correlation decays faster with distance when the hole binding becomes stronger. This is in complete agreement with a recent study by Ivanov, Lee and Wen (Phys. Rev. Lett. 84, 3958, (2000)) based on the SU(2) theory, and strongly suggests that the staggered-flux phase is a key ingredient in the t-J model. We further show that this staggered-flux pattern does not exist in a state where the holes repel each other. Correlations of the chirality operator S_1.(S_2xS_3) show that the staggered pattern of the chirality is closely tied to the holes. 
P. W. Leung