The schematic picture for the superconducting condensation based on the Fermi arc picture. We now extend the momentum angle from 0 to π/2, corresponding to the momentum from (π, 0) to (0, π). The two terminals are corresponding to the anti-nodal points with the maximum gap. While at the angle of 45° it is at the nodal point with zero gap. For an underdoped sample, the length of the Fermi arc is finite and is highlighted by the horizontal dashed line. With more doping, this Fermi arc length becomes longer and longer. Below T_c, a superconducting gap will be formed on these Fermi arcs. This figure is adopted from Refs. [7,8]. The dashed blue line represents the pseudogap. The green solid line shows the energy scales on the terminals of the Fermi arcs.