Pancake vortex molecules in HgBa₂Ca_n-1Cu_nO_y (n ≥ 6) superconductors

HgBa₂Ca_n-1Cu_nO_y (Hg:12(n - 1)n) phases have the same T_c independent of n and the same vortex melting line for n ≥ 6. In these materials, there are two types of pancake pairs: those separated by the thick block of (n - 2) inner CuO₂ planes, which are weakly coupled by the magnetic interaction, and, respectively, those separated by the thin HgBa₂O_x charge reservoir layer, which are much stronger coupled by the Josephson coupling. The vortex melting line common to all Hg:12(n - 1)n phases (n ≥ 6), separates two new vortex phases, pancake-molecule-glass, and pancake-molecule-liquid