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Title: Pseudogap behavior in Bi{sub 2}Ca{sub 2}SrCu{sub 2}O{sub 8}: Results of the generalized dynamical mean-field approach

Abstract

Pseudogap phenomena are observed for the normal underdoped phase of different high-T{sub c} cuprates. Among others, the Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8-{delta}} (Bi2212) compound is one of the most studied experimentally. To describe the pseudogap regime in Bi2212, we use a novel generalized ab initio LDA + DMFT + {sigma}{sub k} hybrid scheme. This scheme is based on the strategy of one of the most powerful computational tools for real correlated materials: the local density approximation (LDA) + dynamical mean-field theory (DMFT). Conventional LDA + DMFT equations are here supplied with an additional (momentum-dependent) self-energy {sigma}{sub k} in the spirit of our recently proposed DMFT + {sigma}{sub k} approach taking into account pseudogap fluctuations. In the present model, {sigma}{sub k} describes nonlocal correlations induced by short-range collective Heisenberg-like antiferromagnetic spin fluctuations. The effective single-impurity problem of the DMFT is solved by the numerical renormalization group (NRG) method. Material-specific model parameters for the effective x{sup 2} - y{sup 2} orbital of Cu-3d shell of the Bi2212 compound, e.g., the values of intra-and interlayer hopping integrals between different Cu sites, the local Coulomb interaction U, and the pseudogap potential {delta} were obtained within the LDA and LDA + DMFT schemes. Here, wemore » report on the theoretical LDA + DMFT + {sigma}{sub k} quasiparticle band dispersion and damping, Fermi surface renormalization, momentum anisotropy of (quasi)static scattering, densities of states, spectral densities, and angular-resolved photoemission (ARPES) spectra, taking into account pseudogap and bilayer splitting effects for normal (slightly) underdoped Bi2212 ({delta} = 0.15). We show that LDA + DMFT + {sigma}{sub k} successfully describes strong (pseudogap) scattering close to Brillouin zone boundaries. Our calculated LDA + DMFT + {sigma}{sub k} Fermi surfaces and ARPES spectra in the presence of pseudogap fluctuations are almost insensitive to the bilayer splitting strength. However, our LDA-calculated value of bilayer splitting is rather small to describe the experimentally observed peak-dip-hump structure. The results obtained are in good semiquantitative agreement with various recent ARPES experiments.« less

Authors:
;  [1];  [2];  [3]
  1. Russian Academy of Sciences, Institute for Electrophysics (Russian Federation)
  2. Russian Academy of Sciences, Institute for Metal Physics (Russian Federation)
  3. Russian Academy of Sciences, Institute for Electrophysics (Russian Federation), E-mail: sadovski@iep.uran.ru
Publication Date:
OSTI Identifier:
21072474
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 104; Journal Issue: 5; Other Information: DOI: 10.1134/S1063776107050135; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANISOTROPY; ANTIFERROMAGNETISM; APPROXIMATIONS; BISMUTH OXIDES; BRILLOUIN ZONES; CALCIUM OXIDES; COPPER OXIDES; CUPRATES; EMISSION SPECTRA; EQUATIONS; FERMI LEVEL; FLUCTUATIONS; HIGH-TC SUPERCONDUCTORS; MEAN-FIELD THEORY; PHOTOEMISSION; RENORMALIZATION; SCATTERING; SELF-ENERGY; SPECTRAL DENSITY; STRONTIUM OXIDES

Citation Formats

Kuchinskii, E. Z., Nekrasov, I. A., Pchelkina, Z. V., and Sadovskii, M. V. Pseudogap behavior in Bi{sub 2}Ca{sub 2}SrCu{sub 2}O{sub 8}: Results of the generalized dynamical mean-field approach. United States: N. p., 2007. Web. doi:10.1134/S1063776107050135.
Kuchinskii, E. Z., Nekrasov, I. A., Pchelkina, Z. V., & Sadovskii, M. V. Pseudogap behavior in Bi{sub 2}Ca{sub 2}SrCu{sub 2}O{sub 8}: Results of the generalized dynamical mean-field approach. United States. doi:10.1134/S1063776107050135.
Kuchinskii, E. Z., Nekrasov, I. A., Pchelkina, Z. V., and Sadovskii, M. V. Tue . "Pseudogap behavior in Bi{sub 2}Ca{sub 2}SrCu{sub 2}O{sub 8}: Results of the generalized dynamical mean-field approach". United States. doi:10.1134/S1063776107050135.
@article{osti_21072474,
title = {Pseudogap behavior in Bi{sub 2}Ca{sub 2}SrCu{sub 2}O{sub 8}: Results of the generalized dynamical mean-field approach},
author = {Kuchinskii, E. Z. and Nekrasov, I. A. and Pchelkina, Z. V. and Sadovskii, M. V.},
abstractNote = {Pseudogap phenomena are observed for the normal underdoped phase of different high-T{sub c} cuprates. Among others, the Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8-{delta}} (Bi2212) compound is one of the most studied experimentally. To describe the pseudogap regime in Bi2212, we use a novel generalized ab initio LDA + DMFT + {sigma}{sub k} hybrid scheme. This scheme is based on the strategy of one of the most powerful computational tools for real correlated materials: the local density approximation (LDA) + dynamical mean-field theory (DMFT). Conventional LDA + DMFT equations are here supplied with an additional (momentum-dependent) self-energy {sigma}{sub k} in the spirit of our recently proposed DMFT + {sigma}{sub k} approach taking into account pseudogap fluctuations. In the present model, {sigma}{sub k} describes nonlocal correlations induced by short-range collective Heisenberg-like antiferromagnetic spin fluctuations. The effective single-impurity problem of the DMFT is solved by the numerical renormalization group (NRG) method. Material-specific model parameters for the effective x{sup 2} - y{sup 2} orbital of Cu-3d shell of the Bi2212 compound, e.g., the values of intra-and interlayer hopping integrals between different Cu sites, the local Coulomb interaction U, and the pseudogap potential {delta} were obtained within the LDA and LDA + DMFT schemes. Here, we report on the theoretical LDA + DMFT + {sigma}{sub k} quasiparticle band dispersion and damping, Fermi surface renormalization, momentum anisotropy of (quasi)static scattering, densities of states, spectral densities, and angular-resolved photoemission (ARPES) spectra, taking into account pseudogap and bilayer splitting effects for normal (slightly) underdoped Bi2212 ({delta} = 0.15). We show that LDA + DMFT + {sigma}{sub k} successfully describes strong (pseudogap) scattering close to Brillouin zone boundaries. Our calculated LDA + DMFT + {sigma}{sub k} Fermi surfaces and ARPES spectra in the presence of pseudogap fluctuations are almost insensitive to the bilayer splitting strength. However, our LDA-calculated value of bilayer splitting is rather small to describe the experimentally observed peak-dip-hump structure. The results obtained are in good semiquantitative agreement with various recent ARPES experiments.},
doi = {10.1134/S1063776107050135},
journal = {Journal of Experimental and Theoretical Physics},
number = 5,
volume = 104,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}