S. Pessaud et F. Gervais, Parametrization of optical conductivity of the prototypic high-T-c cuprateLa2-xSrxCuO4, MAT SCI E B, 86(3), 2001, pp. 200-205
With the aim to propose a description as general as possible of 'non-metall
ic' conducting materials, including the class of high-T-c cuprate supercond
uctors, we test a model based on the generalization of the Lyddane-Sachs-Te
ller relationship on the prototype of the class. This is also an extension
of the conventional Drude model. It is shown to fit closely with the infrar
ed-visible-near ultraviolet reflection spectra of La2-xSrxCuO4 for all x va
rying from 0 to 0.34. Polaron formation is highly suggested for low x and t
he model makes it possible to discriminate the trapped polarons from the mo
bile species. The two- to three-dimensional change of regime is accompanied
by a diffusive non-Drude to conventional pseudo-Drude behavior of the mobi
le charge carriers. (C) 2001 Elsevier Science B.V. All rights reserved.