Aspects of renormalization in finite-density field theory

• Autores: Liam Fitzpatrick, Andrew; Torroba, Gonzalo; Wang, Huajia
• Año de publicación: 2015
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Strongly Correlated Electrons; Heavy Fermions; Finite Density
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

We study the renormalization of the Fermi surface coupled to a massless boson near three spatial dimensions. For this, we set up a Wilsonian RG with independent decimation procedures for bosons and fermions, where the four-fermion interaction “Landau parameters” run already at tree level. Our explicit one-loop analysis resolves previously found obstacles in the renormalization of finite-density field theory, including logarithmic divergences in nonlocal interactions and the appearance of multilogarithms. The key aspects of the RG are the above tree-level running, and a UV-IR mixing between virtual bosons and fermions at the quantum level, which is responsible for the renormalization of the Fermi velocity. We apply this approach to the renormalization of 2kF singularities, and to Fermi surface instabilities in a companion paper, showing how multilogarithms are properly renormalized. We end with some comments on the renormalization of finite-density field theory with the inclusion of Landau damping of the boson.
Fil: Liam Fitzpatrick, Andrew. University of Stanford; Estados Unidos. SLAC National Accelerator Laboratory; Estados Unidos
Fil: Torroba, Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina
Fil: Wang, Huajia. University of Stanford; Estados Unidos