2016/07/31 by Andreas Eberlein, Aavishkar A. Patel, Subir Sachdev
Mathematics · Physics and Astronomy · #Anisotropy #Condensed matter physics #Critical exponent #Critical point (mathematics) #Dimensionless quantity #Exponent #Fermi surface #Geometry #High-Energy Particle Collisions Research #Ising model #Isotropy #Liquid crystal #Mathematical physics #Mathematics #Phase transition #Physics #Physics of Superconductivity and Magnetism #Quantum Chromodynamics and Particle Interactions #Quantum critical point #Quantum mechanics #Quantum phase transition #Quasiparticle #Scaling #cond-mat.str-el #hep-th
paper · pdf · doi:10.1103/physrevb.95.075127
published as Phys. Rev. B 95, 075127 (2017) · Rewritten version with expanded supplement. 17 pages, 4 figures including supplementary material
openalex created_date 2016/08/23 · openalex publication_date 2017/02/15 · arxiv created 2017/02/16 · arxiv updated 2017/02/22 · openalex updated_date 2026/08/06
In an isotropic strongly interacting quantum liquid without quasiparticles, general scaling arguments imply that the dimensionless ratio (kB/\ensuremathℏ)\phantom\rule0.16em0ex\ensuremathη/s, where \ensuremathη is the shear viscosity and s is the entropy density, is a universal number. We compute the shear viscosity of the Ising-nematic critical point of metals in spatial dimension d=2 by an expansion below d=5/2. The anisotropy associated with directions parallel and normal to the Fermi surface leads to a violation of the scaling expectations: \ensuremathη scales in the same manner as a chiral conductivity, and the ratio \ensuremathη/s diverges at low temperature (T) as T^\ensuremath-2/z, where z is the dynamic critical exponent for fermionic excitations dispersing normal to the Fermi surface.