Artículos de revistas
Thermodynamic potential of the periodic Anderson model with the X-boson method: chain approximation
Registro en:
Physica A-statistical Mechanics And Its Applications. Elsevier Science Bv, v. 308, n. 41730, n. 245, n. 255, 2002.
0378-4371
WOS:000176151600020
10.1016/S0378-4371(02)00575-7
Autor
Franco, R
Figueira, MS
Foglio, ME
Institución
Resumen
The periodic Anderson model (PAM) in the U --> infinity limit has been studied in a previous work employing the cumulant expansion with the hybridization as perturbation (Figueira et al., Phys. Rev. B 50 (1994) 17933). When the total number of electrons N-t is calculated as a function of the chemical potential mu in the "chain approximation" (CHA), there are three values of the chemical potential mu for each N-t in a small interval of N-t at low T (Physica A 209 (1994) 279). We have recently introduced the "X-boson" method, inspired in the slave boson technique of Coleman, that solves the problem of nonconservation of probability (completeness) in the CHA as well as removing the spurious phase transitions that appear with the slave boson method in the mean field approximation. In the present paper, we show that the X-boson method solves also the problem of the multiple roots of N-t(mu) that appear in the CHA. (C) 2002 Elsevier Science B.V. All rights reserved. 308 41730 245 255