title: Layer transfer approach to opaline hetero photonic crystals.
abstract: By taking advantage of the hydrophobicity of dry polystyrene colloidal crystal (opal) films and the large surface tension of water, a convectively self-assembled polystyrene opal film on a hydrophilic glass substrate can be peeled off from the substrate and floated on the water surface. A layer transfer technique was developed to sequentially stack floating opal films of different sphere sizes, resulting in opaline hetero photonic crystals. The feasibility of this technique to planar defect engineering in a self-assembled colloidal photonic crystal was also demonstrated. Both structural observation and optical characterization confirmed the crystalline integrity of the resultant opaline heterostructures.
authors.affiliation: Singapore-MIT Alliance, N3.2-01-36, 65 Nanyang Drive, Singapore.
authors.forename: Qingfeng
authors.initials: Q
authors.lastname: Yan
authors.forename: Lay Kuan
authors.initials: LK
authors.lastname: Teh
authors.forename: Qi
authors.initials: Q
authors.lastname: Shao
authors.forename: C C
authors.initials: CC
authors.lastname: Wong
authors.forename: Yet-Ming
authors.initials: YM
authors.lastname: Chiang