Density structure of polymers in the layered host system: the effect of the excluded volume.

We theoretically investigate the density structure of homo-polymers placed inside the host system of alternating layers that have different affinity for polymers. The exact solutions are obtained for the two-point propagator, monomer number density and average Flory radius of the ideal Gaussian polymers immersed in this periodic host structure. For the case where the excluded volume interactions are taken into account, the approximate counterparts of the above exact solutions are found. Based on the comparison of the obtained solutions, the effect of the excluded volume is found to qualitatively change the behaviour of the number density and Flory radius of polymers calculated as a function of the average affinity of the layers and the periodicity of the layered host. The effects (e.g. `polymer localization') of a small number of defects that disturb the perfection of the layered host on the structure of polymers placed in this host are investigated.