Magnitude of spin and charge density wave amplitudes in underdoped cuprates

Self-consistent calculation of spin (charge) density wave (S(C)DW) order pa rameters have been performed for bilayered cuprates on the basis of a singl et-correlated band model. Evolution of the Fermi surface in the strongly un derdoped regime is described by a two-band approach. The smooth development of the pseudogap formation temperature from underdoped to overdoped states is explained and the Fourier amplitudes [s(q)] (spin) and [e(q)] (charge) modulations are calculated. We have found a maximum of the incommensurabili ty for doping 0.09 divided by0.11 holes per copper site.