A new lattice model is presented for correlated electrons on the unrestricted $4^L$-dimensional electronic Hilbert space ${\otimes }_{n=1\mathrm{}}^L{\mathbf{C}}^4$ (where $L$ is the lattice length). It is a supersymmetric generalization of the Hubbard model, but differs from the extended Hubbard model proposed by Essler, Korepin, and Schoutens. The supersymmetry algebra of the new model is superalgebra gl(2 $|$1). The model contains one symmetry-preserving free real parameter which is the Hubbard interaction parameter $U$, and has its origin here in the one-parameter family of inequivalent typical 4-dimensional irreducible representations of gl(2 $|$1). On a one-dimensional lattice, the model is exactly solvable by the Bethe ansatz.

• Received 14 November 1994

DOI:https://doi.org/10.1103/PhysRevLett.74.2768