Evidence for an orbital dependent Mott transition in the ladders of (La, Ca)(x)Sr14-xCu24O41 derived by electron energy loss spectroscopy

Article

关键词: HIGH-TC SUPERCONDUCTIVITY;    SPIN-LADDER;    CHARGE;    HOLE;    CUPRATE;    DYNAMICS;    CRYSTAL;    MODES;    GAP;   

DOI  :  10.1103/PhysRevB.101.195132

来源: SCIE

【 摘 要 】

The knowledge of the charge carrier distribution among the different orbitals of Cu and O is a precondition for the understanding of the physical properties of various Cu-O frameworks. We employ electron energy loss spectroscopy to elucidate the charge carrier plasmon dispersion in (La, Ca)(x)Sr14-xCu24O21 in dependency of x as well as temperature. We observe that the energy of the plasmon increases upon increasing Ca content, which signals an internal charge redistribution between the two Cu-O subsystems. Moreover, contrary to an uncorrelated model we come to the conclusion that the holes transferred to the Cu2O3 ladders are mainly located in the bonding and not in the antibonding band. This is caused by an orbital dependent Mott transition.

【 授权许可】

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