Constructing 3D crystal templates for photonic band gap materials using holographic optical tweezers

• Published in: Optics express Vol. 16; no. 17; pp. 13005 - 13015
• Main Authors: Benito, D C, Carberry, D M, Simpson, S H, Gibson, G M, Padgett, M J, Rarity, J G, Miles, M J, Hanna, S
• Format: Journal Article
• Language: English
• Published: United States 18.08.2008
• Subjects: Crystallization - methods; Equipment Design; Equipment Failure Analysis; Holography - methods; Materials Testing; Optical Tweezers; Optics and Photonics - instrumentation; Photons; Polystyrenes - chemistry; Silicon Dioxide - chemistry
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.16.013005

A simple and robust method is presented for the construction of 3-dimensional crystals from silica and polystyrene microspheres. The crystals are suitable for use as templates in the production of three-dimensional photonic band gap (PBG) materials. Manipulation of the microspheres was achieved using a dynamic holographic assembler (DHA) consisting of computer controlled holographic optical tweezers. Attachment of the microspheres was achieved by adjusting their colloidal interactions during assembly. The method is demonstrated by constructing a variety of 3-dimensional crystals using spheres ranging in size from 3 microm down to 800 nm. A major advantage of the technique is that it may be used to build structures that cannot be made using self-assembly. This is illustrated through the construction of crystals in which line defects have been deliberately included, and by building simple cubic structures.