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Fermi surfaces and Luttinger's theorem in paired fermion systems

Subir Sachdev·Kun Yang
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Abstract

We discuss ground state properties of a mixture of two fermion species which can bind to form a molecular boson. When the densities of the fermions are unbalanced, one or more Fermi surfaces can appear: we describe the constraints placed by Luttinger's theorem on the volumes enclosed by these surfaces in such Bose-Fermi mixtures. We also discuss the nature of the quantum phase transitions involving changes in the number of Fermi surfaces.

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Subir Sachdev, Kun Yang. 2006-05-08. Fermi surfaces and Luttinger's theorem in paired fermion systems. https://doi.org/10.1103/physrevb.73.174504

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