MRI: Development of a Holographic Fabrication and Characterization Instrument for Materials Research and Educational Outreach

New York University, New York NY

Investigators

Abstract

0922680 Grier New York U. "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." Technical Summary: This proposal requests support to develop an integrated all-optical instrument for characterizing fluid-borne objects such as colloidal particles, nanowires and biological cells, and for assembling them into three dimensional structures for applications in materials science and engineering. The instrument is based on two complementary techniques that were developed in the Principal Investigator's laboratory: quantitative holographic video microscopy, and dynamic holographic trapping. The former can track hundreds of moving objects simultaneously with nanometer resolution in three dimensions, while simultaneously measuring their dimensions and optical properties. The latter can trap hundreds of microscopic objects independently and organize them into any specified three-dimensional structure. Together, these core technologies provide unprecedented control over the microscopic world. Optimized optical and mechanical design will enable the proposed instrument to characterize and process materials that are too sensitive or too challenging for existing proof-of-concept instruments. Consequently, it will have immediate applications for rapid prototyping of soft-matter-based photonic, electronic and optical electronic devices, and also will be used for micromechanical assays of bacterial biofilms. Its accessible layout and anticipated ease of use also will facilitate rapid adoption for fundamental research in physics and biophysics. The proposed instrument will be developed and operated out of New York University?s Center for Soft Matter Research, and will serve as a core facility for NYU?s recently inaugurated Materials Research Science and Engineering Center. Its open and modular design and robust computer-driven interface will be ideal for hands-on demonstrations during regularly scheduled K-12 classroom visits to the CSMR laboratories, and will be featured in the award-winning Scientific Frontiers educational outreach program at NYU. Non-Technical Summary: Assembling microscopic building blocks into three-dimensional functional structures is one of the outstanding challenges of materials science. Picking the right objects out of chemically synthesized mixtures, putting them together, and verifying the outcome has been all but impossible. The proposed instrument addresses the assembly problem by using forces exerted by computer-generated holograms to arrange microscopic fluid-borne objects into any specified three-dimensional configuration. It complements this holographic optical trapping capability with video-rate holographic imaging to track the objects? motions in three dimensions and simultaneously to measure their physical properties, thereby solving the selection and verification problems. Together, holographic micromanipulation and holographic characterization make it possible to build up complex three-dimensional structures from chemically-synthesized components. Immediate applications include assembling optically active colloidal spheres into artificial opals with optically-switchable optical properties, building three-dimensional circuits out of chemically grown nanowires, and crafting microscopic lasers out of colloidal components. The same instrument also will used to study the micromechanical properties of bacterial biofilms. The proposed instrument?s unique combination of capabilities will provide a core facility for New York University?s recently awarded Materials Research Science and Engineering Center. It also will take center stage in NYU?s award-winning Scientific Frontiers Program, which annually hosts hands-on laboratory tours for hundreds of New York City K-12 schoolchildren. The instrument?s open design, real-time visual feedback and robust computer-driven interface will encourage students of all ages to reach into the microscopic world and explore.