Composite fermions and quartets in the Fermi-Bose mixture with attractive interaction between fermions and bosons

M. Yu. Kagan; I. V. Brodsky; D. V. Efremov; A. V. Klaptsov

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Composite fermions and quartets in the Fermi-Bose mixture with attractive interaction between fermions and bosons

M. Yu. Kagan·I. V. Brodsky·D. V. Efremov·A. V. Klaptsov

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Abstract

We consider a model of Fermi-Bose mixture with strong hard-core repulsion between particles of the same sort and attraction between particles of different sorts. In this case, besides the standard anomalous averages of the type $ $; $ $ and $ $, a pairing between fermion and boson of the type $bc$ is possible. This pairing corresponds to a creation of composite fermions in the system. At low temperatures and equal densities of fermions and bosons composite fermions are further paired in quartets. Our investigations are important for high-$T_c$ superconductors and in connection with recent observation of weakly bound dimers in magnetic traps at ultralow temperatures.

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M. Yu. Kagan, I. V. Brodsky, D. V. Efremov, A. V. Klaptsov. 2004-03-03. Composite fermions and quartets in the Fermi-Bose mixture with attractive interaction between fermions and bosons. https://arxiv.org/abs/cond-mat/0209481

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