“…The FP potential [ 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 ] is a function of overlap Q , a weighted average over the system of the two-point correlation function, and plays the same role as the Landau free energy of a global parameter Q that indicates a distance between the two copies in configuration space. Theoretical and simulation studies have demonstrated that the FP potential reproduces the temperature evolution of FELs, just like the Landau free energy [ 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 ]. With decreasing temperature, the FP potential develops a secondary minimum for representing a metastable state.…”