Anomalous criticality near semimetal-to-superfluid quantum phase transition in a two-dimensional Dirac cone model

作者：Obert Benjamin; Takei So; Metzner Walter^*

来源：Annalen der Physik, 2011, 523(8-9): 621-628.

DOI：10.1002/andp.201100039

• Correlated electrons
• quantum criticality
• non-Fermi liquid

We analyze the scaling behavior at and near a quantum critical point separating a semimetallic from a superfluid phase. To this end we compute the renormalization group flow for a model of attractively interacting electrons with a linear dispersion around a single Dirac point. We study both ground state and finite temperature properties. In two dimensions, the electrons and the order parameter fluctuations exhibit power-law scaling with anomalous scaling dimensions. The quasi-particle weight and the Fermi velocity vanish at the quantum critical point. The order parameter correlation length turns out to be infinite everywhere in the semimetallic ground state.

• 出版日期2011-8