Supersymmetry in models with strong on-site Coulomb repulsion: Application to the Heisenberg model
نویسندگان
چکیده
A supersymmetric way of imposing the constraint of no double occupancy in models with strong on-site Coulomb repulsion is presented in this paper. In this formulation the physical operators in the constrainted Hilbert space are invariant under local unitary transformations mixing boson and fermion representations. To illustrate, the formulation is applied to the Heisenberg, t-J , and infinite-U Anderson models. In particular, we study the Heisenberg model carefully in two dimensions where results on spin excitation spectrum are presented. @S0163-1829~99!50210-5#
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تاریخ انتشار 1999