Dynamical susceptibility near a long-wavelength critical point with a nonconserved order parameter
Dynamical susceptibility near a long-wavelength critical point with a nonconserved order parameter
We study the dynamic response of a two-dimensional system of itinerant fermions in the vicinity of a uniform ($\mathbf{Q}=0$) Ising nematic quantum critical point of $d-$wave symmetry. The nematic order parameter is not a conserved quantity, and this permits a nonzero value of the fermionic polarization in the $d-$wave channel …