We have experimentally compared the excitonic properties of hybrid multiple quantum wells, (C${}_{\text{6}}$H${}_{\text{5}}$-C${}_{\text{2}}$H${}_{\text{4}}$NH${}_{\text{3}}$)${}_{\text{2}}$PbBr${}_{\text{4}}$ and (C${}_{\text{4}}$H${}_{\text{9}}$NH${}_{\text{3}}$)${}_{\text{2}}$PbBr${}_{\text{4}}$, using photoluminescence, reflection, and photoluminescence excitation measurements. We focused on the contribution of the image charge effect (ICE) to the excitonic energy structure in these materials which have different dielectric constants of the barrier layers. We have found that the binding energies of the $2s$ and $3s$ excitons are considerably enhanced by ICE, while the contribution of ICE to the $1s$ excitons is smaller because of the small Bohr radius, which is comparable to the well width.

• Received 30 August 2012

DOI:https://doi.org/10.1103/PhysRevB.87.125421