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Complete Pseudohole and Heavy-Pseudoparticle Operator Representation for the Hubbard Chain

J. M. P. Carmelo·N. M. R. Peres
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Abstract

We introduce the pseudohole and heavy-pseudoparticle operator algebra that generates all Hubbard-chain eigenstates from a single reference vacuum. In addition to the pseudoholes already introduced for the description of the low-energy physics, this involves the heavy pseudoparticles associated with Hamiltonian eigenstates whose energy spectrum has a gap relatively to the many-electron ground state. We introduce a generalized pseudoparticle perturbation theory which describes the relevant finite-energy ground state transitions. In the present basis these excitations refer to a small density of excited pseudoparticles. Our operator basis goes beyond the Bethe-ansatz solution and it is the suitable and correct starting point for the study of the finite-frequency properties, which are of great relevance for the understanding of the unusual spectral properties detected in low-dimensional novel materials.

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J. M. P. Carmelo, N. M. R. Peres. 1997-07-02. Complete Pseudohole and Heavy-Pseudoparticle Operator Representation for the Hubbard Chain. https://doi.org/10.1103/physrevb.56.3717

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