THE ESSENTIAL CHARACTERISTICS OF THE PSEUDOGAPPED METALLIC STATE OF HIGH-T-C SUPERCONDUCTOR

The pseudogapped metallic state which was recently revealed by angle-r esolved photoemission experiments in the normal state of high-T-c supe rconductor (NTS) can be interpreted with a model of non-simple metal i n which there are locally correlating carrier pairs and the coexisting single itinerant carriers. The pair correlation is temperature depend ent with a delocalization process with decreasing temperature down to T-c, which can be revealed by the thermoelectric power S of HTS. By th eoretical calculation, it is shown that a pseudogap exists in electron ic energy spectrum of this two-component system in which high T-c and small superconducting coherence length can be obtained in its supercon ducting state.