Spinon-holon attraction in the supersymmetric t−j model with 1/r² interaction

We derive the coordinate representation of the one-spinon one-holon wave function for the supersymmetric t−J model with 1/r² interaction. This result allows us to show that a spinon and a holon attract each other at short distance. The attraction gets stronger as the size of the system is increased and, in the thermodynamic limit, it is responsible for the square-root singularity in the hole spectral function [Y. Kato, Phys. Rev. Lett. 81, 5402 (1998)].