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arXiv · 1903.05013

Generalized Falicov-Kimball Models

Xiao-Hui Li·Zewei Chen·Tai-Kai Ng
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Abstract

In this paper we extend the Falicov-Kimball model (FKM) to the case where the "quasi-particles" entering the FKM are not "ordinary" fermions. As an example we first discuss how the FKM can be generalized to the case with spin-dependent hopping. Afterwards we discuss several cases where the "quasi-particles" entering the FKM are Majorana fermions (extended Majorana-Falicov-Kimball Model (MFKM). Two examples of extended MFKM are discussed in detail: (i) a $p$-wave BCS superconductor on a bipartite lattice and (ii) a BCS-Anderson model. We also discuss the most general forms of extended MFKM, including a brief discussion on the case where the Majorana fermions represent spins, but not real fermion particles.

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Xiao-Hui Li, Zewei Chen, Tai-Kai Ng. 2019-03-12. Generalized Falicov-Kimball Models. https://doi.org/10.1103/physrevb.100.094519

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