Europhys. Lett.
Volume 67, Number 6, September 2004
Page(s) 1011 - 1017
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 01 September 2004
Europhys. Lett., 67 (6), pp. 1011-1017 (2004)
DOI: 10.1209/epl/i2004-10158-9

Luttinger-liquid phenomenology and angle-resolved photoemission for single-layer $\chem{Bi_2Sr}$ 2-x $\chem{La}$ x $\chem{CuO}$ $_{6+\delta}$ high-temperature superconductor

K. Byczuk1, C. Janowitz2, R. Manzke2, J. Spalek3 and W. Wójcik4

1  Institute of Theoretical Physics, Warsaw University ul. Hoza 69, 00-681 Warszawa, Poland
2  Humboldt Universität, Institute für Physik - Newtonstr. 15, 12489 Berlin, Germany
3  Institute of Physics, Jagiellonian University - ul. Reymonta 4, 30-059 Kraków, Poland
4  Institute of Physics, Cracow University of Technology ul. Podchorazych 1, 30-084 Krakow, Poland

(Received 24 May 2004; accepted in final form 27 July 2004)

Recently observed splitting in angular-resolved photoemission spectroscopy (ARPES) on $\chem{Bi_2Sr}$ 2-x $\chem{La}$ x $\chem{CuO}$ $_{6+\delta}$ high-temperature superconductor (Janowitz C. et al. , Europhys. Lett. 60 (2002) 615) is interpreted within the phenomenological Luttinger-liquid framework, in which both the non-Fermi-liquid scaling exponent of the spectral function and the spin-charge separation are introduced. The anomalous Green function with adjustable parameters fits very well to the Fermi edge and to the low-energy part of ARPES along the $\Gamma$- M line in the Brillouin zone. In contrast to one-dimensional models with Luttinger-liquid behavior, we find that both the anomalous scaling $\alpha$ and the parameter $\delta$ describing the spin-charge separation are momentum dependent. The higher-energy part of the spectra is not accounted for by this simple Luttinger-liquid form of the Green function. In this energy regime, additional scattering processes are plausible to produce the experimentally observed wide incoherent background, which diminishes as the inverse of the energy.

74.72.-h - Cuprate superconductors (high- $T_{\ab{c}}$ and insulating parent compounds).
79.60.-i - Photoemission and photoelectron spectra.
71.10.Hf - Non-Fermi-liquid ground states, electron phase diagrams and phase transitions in model systems.

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