Spin–charge gauge compositeness of electron in HTS: Hints from metal–insulator crossover and entropy behavior Original Research Article

We show that the coexistence of Fermi arcs and metal–insulator crossover of the in-plane resistivity can give a hint of a peculiar “gauge compositeness” of the electron in hole-doped high TcTc cuprates and a similar hint also comes from the negative intercept at T=0T=0 of the electronic entropy extrapolated from moderate temperatures in the “pseudogap phase”. An implementation of this “compositeness” within the spin–charge gauge approach is outlined and is employed to discuss the above phenomena.