Kinetic energy driven superconductivity in doped cuprates

Abstract

Within the $t\ensuremath{-}J$ model, the mechanism of superconductivity in doped cuprates is studied based on the partial charge-spin separation fermion-spin theory. It is shown that dressed holons interact, occurring directly through the kinetic energy by exchanging dressed spinon excitations, leading to a net attractive force between dressed holons; then the electron Cooper pairs originating from the dressed holon pairing state are due to the charge-spin recombination, and their condensation reveals the superconducting ground state. The electron superconducting transition temperature is determined by the dressed holon pair transition temperature and is proportional to the concentration of doped holes in the underdoped regime. With the common form of the electron Cooper pair, we also show that there is a coexistence of the electron Cooper pair and antiferromagnetic short-range correlation, and hence the antiferromagnetic short-range fluctuation can persist into the superconducting state. Our results are qualitatively consistent with experiments.