Possible insulating, metallic and superconducting states in doped high-Tc superconductors

We have determined the possible insulating, metallic and superconducting (SC) states and temperature- and doping-induced electronic phase transitions in doped high-Tc superconductors (HTSC), going beyond the conventional theories of insulators, metals and superconductors. Using the continuum theory of real (r)-space (bi)polarons and the novel Fermi–Bose-liquid theory of superconductivity, we show that r- and k-space (bi)polarons are relevant entities in underdoped, optimally doped and some overdoped HTSC, and quasi-free carriers and cooperons exist in overdoped HTSC. Generic and complete quantitative temperature-doping phase diagrams of cuprates with eight electronic states are presented.