Lax pair for SU(n) Hubbard model

For one dimensional SU(n) Hubbard model, a pair of Lax operators are derived, which give a set of fundamental equations for the quantum inverse scattering method under both periodic and open boundary conditions. This provides another proof of the integrability of the model under periodic boundary condition.Comment: Latex file, 7 pages, little change adde

Fermionic R-Operator and Integrability of the One-Dimensional Hubbard Model

We propose a new type of the Yang-Baxter equation (YBE) and the decorated Yang-Baxter equation (DYBE). Those relations for the fermionic R-operator were introduced recently as a tool to treat the integrability of the fermion models. Using the YBE and the DYBE for the XX fermion model, we construct the fermionic R-operator for the one-dimensional (1D) Hubbard model. It gives another proof of the integrability of the 1D Hubbard model. Furthermore a new approach to the SO(4) symmetry of the 1D Hubbard model is discussed.Comment: 25 page

Fermionic R-operator approach for the small-polaron model with open boundary condition

Exact integrability and algebraic Bethe ansatz of the small-polaron model with the open boundary condition are discussed in the framework of the quantum inverse scattering method (QISM). We employ a new approach where the fermionic R-operator which consists of fermion operators is a key object. It satisfies the Yang-Baxter equation and the reflection equation with its corresponding K-operator. Two kinds of 'super-transposition' for the fermion operators are defined and the dual reflection equation is obtained. These equations prove the integrability and the Bethe ansatz equation which agrees with the one obtained from the graded Yang-Baxter equation and the graded reflection equations.Comment: 10 page

Analytic Bethe Ansatz for 1-D Hubbard model and twisted coupled XY model

We found the eigenvalues of the transfer matrices for the 1-D Hubbard model and for the coupled XY model with twisted boundary condition by using the analytic Bethe Ansatz method. Under a particular condition the two models have the same Bethe Ansatz equations. We have also proved that the periodic 1-D Hubbard model is exactly equal to the coupled XY model with nontrivial twisted boundary condition at the level of hamiltonians and transfer matrices.Comment: 22 pages, latex, no figure

Valores de referencia en el número de autores en las mejores publicaciones de revistas científicas en el área de las ciencias de la actividad física y del deporte

The purpose of this study is to analyze the number of authors of the articles in the sciences of physical activity and sport in the Web of Science. Ten artices with more citations of the 10 journals with the highest impact factor in 2012 (JCR), the thematic area «Sport Science» and the 10 articles with more citations of the 10 related journals were analyzed sports science, with highest impact in 2012 (JCR) of area «Hospitality Leisure sport Tourism». The most significant results indicated that: a) the average number of authors in the journals of the subject area «Sport Science», is 3-4 authors, while in the related sports science journals Area «Hospitality Leisure Sport Tourism «is between 2-3 authors. These data may serve as reference both evaluators as assessed in different criteria.El propósito del presente estudio es analizar el número de autores de los principales artículos relacionados con las ciencias de la actividad física y del deporte de la Web of Science. Para ello se analizaron los 10 artículos con mayor número de citas de las 10 revistas con mayor índice de impacto del año 2012 (JCR), del área temática “Sport Science” y los 10 artículos con mayor número de citas de las 10 revistas relacionadas con las ciencias del deporte, con mayor índice de impacto del año 2012 (JCR), del Área “Hospitality Leisure Sport Tourism”. Los resultados más significativos señalaron que: a) el número medio de autores en las revistas del área temática “Sport Science”, está entre 3-4 autores, mientas que en las revistas relacionadas con las ciencias del deporte del Área “Hospitality Leisure Sport Tourism”, se sitúa entre 2-3 autores. Estos datos pueden servir de referencia tanto a evaluadores como a evaluados en sus diferentes criterios

Fermionic R-Operator and Algebraic Structure of 1D Hubbard Model: Its application to quantum transfer matrix

The algebraic structure of the 1D Hubbard model is studied by means of the fermionic R-operator approach. This approach treats the fermion models directly in the framework of the quantum inverse scattering method. Compared with the graded approach, this approach has several advantages. First, the global properties of the Hamiltonian are naturally reflected in the algebraic properties of the fermionic R-operator. We want to note that this operator is a local operator acting on fermion Fock spaces. In particular, SO(4) symmetry and the invariance under the partial particle hole transformation are discussed. Second, we can construct a genuinely fermionic quantum transfer transfer matrix (QTM) in terms of the fermionic R-operator. Using the algebraic Bethe Ansatz for the Hubbard model, we diagonalize the fermionic QTM and discuss its properties.Comment: 22 pages, no figure

Exact diagonalization of the generalized supersymmetric t-J model with boundaries

We study the generalized supersymmetric $t-J$ model with boundaries in three different gradings: FFB, BFF and FBF. Starting from the trigonometric R-matrix, and in the framework of the graded quantum inverse scattering method (QISM), we solve the eigenvalue problems for the supersymmetric $t-J$ model. A detailed calculations are presented to obtain the eigenvalues and Bethe ansatz equations of the supersymmetric $t-J$ model with boundaries in three different backgrounds.Comment: Latex file, 32 page

Commuting quantum transfer matrix approach to intrinsic Fermion system: Correlation length of a spinless Fermion model

The quantum transfer matrix (QTM) approach to integrable lattice Fermion systems is presented. As a simple case we treat the spinless Fermion model with repulsive interaction in critical regime. We derive a set of non-linear integral equations which characterize the free energy and the correlation length of $$ for arbitrary particle density at any finite temperatures. The correlation length is determined by solving the integral equations numerically. Especially in low temperature limit this result agrees with the prediction from conformal field theory (CFT) with high accuracy.Comment: 17 page

Jordan-Wigner fermionization for the one-dimensional Bariev model of three coupled XY chains

The Jordan-Wigner fermionization for the one-dimensional Bariev model of three coupled XY chains is formulated. The Lax operator in terms of fermion operators and the quantum R-matrix are presented explicitly. Furthermore, the graded reflection equations and their solutions are discussed.Comment: 10 pages, no figur