Composite-Fermion Theory for Pseudogap, Fermi Arc, Hole Pocket, and Non-Fermi-Liquid of Underdoped Cuprate Superconductors

摘要

We propose that an extension of the exciton concept to doped Mott insulatorsoffers a fruitful insight into challenging issues of the copper oxidesuperconductors. In our extension, new fermionic excitations called cofermionsemerge in conjunction to generalized excitons. The cofermions hybridize withconventional quasiparticles. Then a hybridization gap opens, and is identifiedas the pseudogap observed in the underdoped cuprates. The resultantFermi-surface reconstruction naturally explains a number of unusual propertiesof the underdoped cuprates, such as the Fermi arc and/or pocket formation.