PHOTOEXCITATIONS IN CONJUGATED POLYMER SUPERLATTICES

We present evidence of quantum confinement of the photo-generated stat es in a conjugated block copolymer consisting of regularly alternating thiophenic and phenylenic moieties of various lengths, thus giving ri se to a sort of one-dimensional superperiodicity. CW photoinduced spec tra (both in the infrared and in the visible) have revealed localizati on effects when the width of the potential well exceeds five thiopheni c rings. A discussion of the new features in the copolymer photoexcita tion spectrum with respect to the parent polymers is also presented.