REPRESENTATION OF THE T-J MODEL USING DECOUPLED SPIN AND CHARGE VARIABLES

Using the mapping of the single-occupation space of the t-J model onto the tensor-product space of local spin-1/2 and holon states, the Hubb ard operators and their products corresponding to physical quantities are expressed in terms of local spin and holon operators. All relevant operator relations of the t-J model are reproduced by this representa tion and no projection procedure is needed to remove the redundant deg rees of freedom originating from the spin and charge decoupling. It is shown that the time-reversal symmetry requirement makes the essential restriction on rile choice of the fictitious spin start associated wi th the electron-vacancy state in the mapping. The results are critical ly compared with the treatment of this topic in the paper of Wang and Rice [Phys.Rev.B49,4360 (1994)].