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arXiv · 2010.00444

Study of the Kondo and high-temperature limits of the slave-boson and X-boson methods

Lizardo H. C. M. Nunes·M. S. Figueira·M. E. Foglio
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Abstract

In this Letter we study the periodic Anderson model, employing both the slave-boson and the X-boson approaches in the mean field approximation. We investigate the breakdown of the slave-boson at intermediate temperatures when the total occupation number of particles Nt = Nf + Nc is keep constant, where Nf and Nc are respectively the occupation numbers of the localized and conduction electrons, and we show that the high-temperature limit of the slave-boson is Nf = Nc = Nt /2. We also compare the results of the two approaches in the Kondo limit and we show that at low-temperatures the X-boson exhibits a phase transition, from the Kondo heavy fermion (K-HF) regime to a local moment magnetic regime (LMM).

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Lizardo H. C. M. Nunes, M. S. Figueira, M. E. Foglio. 2020-09-25. Study of the Kondo and high-temperature limits of the slave-boson and X-boson methods. https://doi.org/10.1016/j.physleta.2006.05.025

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