Infrared absorption spectra of various doping states in cuprate superconductors

Conference · Sat Feb 01 04:00:00 EST 1992

OSTI ID:10121562

Yonemitsu, K; Bishop, A R ^[1]; Lorenzana, J ^[2]

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1. Los Alamos National Lab., NM (United States)
2. International School of Advanced Studies, Trieste (Italy)

Doping states in a two-dimensional three-band extended Peierls-Hubbard model was investigated within inhomogeneous Hartree-Fock and random phase approximation. They are very sensitive to small changes of interaction parameters and their distinct vibrational and optical absorption spectra can be used to identify different doping states. For electronic parameters relevant to cuprate superconductors, as intersite electron-phonon interaction strength increases, the doping state changes from a Zhang-Rice state to a covalent molecular singlet state accompanied by local quenching of the Cu magnetic moment and large local lattice distortion in an otherwise undistorted antiferromagnetic background. In a region where both intersite electron-phonon interaction and on-site electron-electron repulsion are large, we obtain new stable global phases including a bond-order-wave state and a mixed state of spin-Peierls bonds and antiferromagnetic Cu spins, as well as many metastable states. Doping in the bond-order-wave region induces separation of spin and charge. 9 refs.

• Research Organization: Los Alamos National Lab., NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 10121562
• Report Number(s): LA-UR--92-342; CONF-920141--1; ON: DE92007413
• Country of Publication: United States
• Language: English

Related Subjects

665412
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CHARGE DISTRIBUTION
COPPER OXIDES
HARTREE-FOCK METHOD
HIGH-TC SUPERCONDUCTORS
INFRARED SPECTRA
MATHEMATICAL MODELS
SPIN
SUPERCONDUCTING DEVICES
SUPERCONDUCTIVITY