Spectral Function and Quasiparticle Damping of Interacting Bosons in Two Dimensions

Journal Article · Fri Mar 27 00:00:00 EDT 2009 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.102.120601· OSTI ID:21180309

Sinner, Andreas; Kopietz, Peter ^[1]; Hasselmann, Nils ^[2]

---

1. Institut fuer Theoretische Physik, Universitaet Frankfurt, Max-von-Laue-Strasse 1, 60438 Frankfurt (Germany)
2. International Center for Condensed Matter Physics, Universidade de Brasilia, Caixa Postal 04667, 70910-900 Brasilia, DF (Brazil)

We employ the functional renormalization group to study dynamical properties of the two-dimensional Bose gas. Our approach is free of infrared divergences, which plague the usual diagrammatic approaches, and is consistent with the exact Nepomnyashchy identity, which states that the anomalous self-energy vanishes at zero frequency and momentum. We recover the correct infrared behavior of the propagators and present explicit results for the spectral line shape, from which we extract the quasiparticle dispersion and dampi0008.

• OSTI ID: 21180309
• Journal Information: Physical Review Letters, Vol. 102, Issue 12; Other Information: DOI: 10.1103/PhysRevLett.102.120601; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BOSE-EINSTEIN GAS
DISPERSIONS
INFRARED DIVERGENCES
INTERACTING BOSON MODEL
PROPAGATOR
RENORMALIZATION
SELF-ENERGY
SPECTRAL FUNCTIONS
TWO-DIMENSIONAL CALCULATIONS