| Abstract
| - The crystallization of monodisperse polymer latices in a vertical meniscus enables the buildup of functional photonic crystals. Multilayers of colloidal crystal layers have been fabricated that concern aspects as thermal stability and lability (see photograph) as well as chemical variety that can be employed.
- This paper describes ways to multilayer opaline films (opaline heterostructures) composedfrom functional opal layers of spheres with different lattice constants. At first variousmonodisperse colloidsboth cross-linked and un-cross-linkedwere prepared from methylmethacrylate, methyl α-chloroacrylate, and methyl α-bromoacrylate. These colloids can becrystallized into large, well-oriented opaline films with the help of a “drawing apparatus”by the method of crystallization in a moving meniscus. After annealing, a second opalinefilm can be crystallized on top of these films and so on. Electron microscopy inspection showsa sharp borderline between the sublayers and no disorder on both sides although the latticeconstants in both films can be incommensurable. Transmission and reflection measurementsprove the high quality of the films. The use of a combination of thermolabile and thermostablecolloids opens the possibility to prepare functional opaline heterostructures.
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