Fig. 1: Superconductivity at the nematic QCP(δ = 0).
From: Unconventional superconductivity near a nematic instability in a multi-orbital system
a We plot the absolute value of the SC gap scaled by the transition temperature Tc, Δh/Tc(blue) on the hole pocket at zero temperature as a function of the angle on the Fermi surface(green disk) with radius 3 unit. The gap is exponentially small near the cold spots(red dots) while maximum along the kx and ky axis. In (b), we plot the angular variation of the gap, ∣Δh∣/Tc on the hole pocket for three different reduced temperatures, t = 0.9, 0.7 and 0 below the transition point Tc. At finite temperature, the gap vanishes on the four patches of the Fermi surface arcs(flat segments of the gap). In (c), we plot the width of the gap, θ0(T) as a function of the reduced temperature t = T/Tc. We keep the coupling strength g = 1 here.
