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Pseudofermion scattering theory

J. M. P. Carmelo·D. Bozi·P. D. Sacramento
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Abstract

In this paper we study the scattering theory associated with the pseudofermion dynamical theory for the Hubbard chain. In terms of pseudofermions the spectral properties are controlled by zero-momentum forward scattering only. The pseudofermion $S$ matrix is expressed as a commutative product of $S$ matrices, each corresponding to an elementary two-pseudofermion scattering event. This commutative factorization is stronger than the usual factorization associated with Yang-Baxter Equation for the original spin 1/2 electron bare $S$ matrix. Our results reveal the scattering mechanisms which control the exotic finite-energy spectral properties of the low-dimensional complex materials and correlated systems of cold fermionic atoms on an optical lattice. Importantly, the exotic scatterers and scattering centers predicted by the theory were observed by angle-resolved photoelectron spectroscopy in low-dimensional organic metals.

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J. M. P. Carmelo, D. Bozi, P. D. Sacramento. 2006-03-24. Pseudofermion scattering theory. https://arxiv.org/abs/cond-mat/0603665

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