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- Fleck, Marcus, et al.
(författare)
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Dynamical Mean-Field Theory for Doped Antiferromagnets
- 1998
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Ingår i: Physical Review Letters. - 1079-7114. ; 80, s. 2393-2393
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Tidskriftsartikel (refereegranskat)abstract
- We have generalized the dynamical mean-field theory to study the doping dependence of the crossover from antiferromagnetic to short-range order modeled by an incommensurate spin density wave in the Hubbard model. The local self-energy which includes spin fluctuations gives quasiparticle weights and spectral properties in good agreement with quantum Monte Carlo and exact diagonalization data in two dimensions. The spectra at finite doping are characterized by a Mott-Hubbard “gap” accompanied by a pseudogap induced by the local spin order.
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| 2. |
- Fleck, Marcus, et al.
(författare)
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Optical properties of doped antiferromagnets
- 1999
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Ingår i: Journal of Superconductivity. - 0896-1107. ; 12:1, s. 147-149
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the consequences of an incommensurate magnetic order in doped La2-xSrxCuO4 using dynamical mean-field theory for the effective single-band model. The high-energy optical transitions are due to high-energy excitations across large Mott-Hubbard 'gap,' while low-energy excitations involve a pseudogap induced by the local spin order. The latter lead to a strong drop in the scattering rate at low ω, in qualitative agreement with the experimental data.(16 refs)
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| 3. |
- Fleck, M., et al.
(författare)
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Quasiparticle broadening in insulating copper oxides
- 1999
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Ingår i: Physica B. ; 259-261, s. 729-731
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Tidskriftsartikel (refereegranskat)abstract
- We calculate the spectral function of the half-filled two-dimensional Hubbard model with realistic hopping integrals for Sr2CuO2Cl2 within the dynamical mean-field theory at finite temperatures. It is shown that precursor effects of incommensurate spin dynamics lead to an incoherent broadening of the quasiparticle peaks on an energy scale that depends on local spin order. This might serve as an indirect method of detecting changes of local spin order under doping.
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| 4. |
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