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Quasiparticle Properties in Effective Field Theory

L. Platter·H. -W. Hammer·Ulf-G. Meißner
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Abstract

The quasiparticle concept is an important tool for the description of many-body systems. We study the quasiparticle properties for dilute Fermi systems with short-ranged, repulsive interactions using effective field theory. We calculate the proper self-energy contributions at order (K_f/Lambda)^3, where Lambda is the short-distance scale that sets the size of the effective range parameters and K_f the Fermi momentum. The quasiparticle energy, width, and effective mass to order O(K_f/Lambda)^3 are derived from the calculated self-energy.

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L. Platter, H. -W. Hammer, Ulf-G. Meißner. 2002-08-27. Quasiparticle Properties in Effective Field Theory. https://doi.org/10.1016/s0375-9474(02)01365-9

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