We study the scaling behaviour of the optical conductivity (σ) , free energy density (F) and shear viscosity of the quantum critical point associated with spin density wave phase transition for a two-dimensional metallic system with C2 symmetry. A non-Fermi liquid behaviour emerges at two pairs of isolated points on the Fermi surface due to the coupling of a bosonic order parameter to fermionic excitations at those so-called "hot-spots". We find that near the hot-spots, σ and F obey the scalings expected for such an anisotropic system, and the direction-dependent viscosity to entropy density ratio is not a universal number due to the anisotropy. Lastly, we also estimate the effect of the fermion-boson coupling at the hot-spots on superconducting instabilities.
Annals of Physics
- Pub Date:
- January 2017
- Non-Fermi-liquid SDW anisotropic scaling;
- Condensed Matter - Strongly Correlated Electrons;
- High Energy Physics - Theory
- typos in some equations corrected