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All-optical control of microfluidic components using form birefringence


The reflection and refraction of light at a dielectric interface gives rise to forces due to changes in the photon momentum1. At the microscopic level, these forces are sufficient to trap and rotate microscopic objects2,3. Such forces may have a profound impact in the emergent area of microfluidics, where there is the desire to process minimal amounts of analyte. This places stringent criteria on the ability to pump, move and mix small volumes of fluid, which will require the use of micro-components and their controlled actuation4,5,6,7. We demonstrate the modelling, fabrication and rotation of microgears based on the principle of form birefringence. Using a geometric anisotropy (a one-dimensional photonic crystal etched into the microgear), we can fabricate microgears of known birefringence, which may be readily rotated by manipulating the input polarization in a standard optical trap. This methodology offers a new and powerful mechanism for generating a wide range of microfabricated machines, such as micropumps, that may be driven by purely optical control.

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Figure 1: Form birefringent microgears.
Figure 2: Modelling the birefringence.
Figure 3: Fabrication of a microgear.
Figure 4: Rotation results.

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  1. Ashkin, A., Dziedzic, J. M., Bjorkholm, J. E. & Chu, S. Observation of a single-beam gradient force optical trap for dielectric particles. Optics Lett. 11, 288–290 (1986).

    Article  CAS  Google Scholar 

  2. Paterson, L. et al. Controlled rotation of optically trapped microscopic particles. Science 292, 912–914 (2001).

    Article  CAS  Google Scholar 

  3. Friese, M. E. J., Nieminen, T. A., Heckenberg, N. R. & Rubinsztein-Dunlop, H. Optical alignment and spinning of laser-trapped microscopic particles. Nature 394, 348–350 (1998).

    Article  CAS  Google Scholar 

  4. Terray, A., Oakey, J. & Marr, D. W. M. Microfluidic control using colloidal devices. Science 296, 1841–1844 (2002).

    Article  CAS  Google Scholar 

  5. Gauthier, R. C., Tait, R. N. & Ubriaco, M. Activation of microcomponents with light for micro-electro-mechanical systems and micro-optical-electro-mechanical systems applications. Appl. Optics 41, 2361–2367 (2002).

    Article  Google Scholar 

  6. Friese, M. E. J., Rubinsztein-Dunlop, H., Gold, J., Hagberg, P. & Hanstorp, D. Optically driven micromachine elements. Appl. Phys. Lett. 78, 547–549 (2001).

    Article  CAS  Google Scholar 

  7. Maruo, S., Ikuta, K. & Korogi, H. Force-controllable, optically driven micromachines fabricated by single-step two-photon micro stereolithography. J. Microelectromech. Syst. 12, 533–539 (2003).

    Article  Google Scholar 

  8. Higurashi, E. et al. Optically induced rotation of anisotropic micro-objects fabricated by surface machining. Appl. Phys. Lett. 64, 2209–2210 (1994).

    Article  CAS  Google Scholar 

  9. Higurashi, E., Ohguchi, O., Ukita, H. & Sawada, R. Optically induced rotation of disysymmetrically shaped fluorinated polyimide micro-objects in optical traps. J. Appl. Phys. 82, 2773–2779 (1997).

    Article  CAS  Google Scholar 

  10. Galajda, P. & Ormos, P. Complex micromachines produced and driven by light. Appl. Phys. Lett. 78, 249–251 (2001).

    Article  CAS  Google Scholar 

  11. Born, M. & Wolf, E. Principles of Optics 6th edn, Section 14.5.2 (Cambridge Univ. Press, Cambridge, 1980).

    Google Scholar 

  12. Bishop, A. I., Nieminen, T. A., Heckenberg, N. R. & Rubinsztein-Dunlop, H. Optical application and measurement of torque on microparticles of isotropic nonabsorbing material. Phys. Rev. A 68, 033802 (2003).

    Article  Google Scholar 

  13. Nieminen, T. A., Heckenberg, N. R. & Rubinsztein-Dunlop, H. Optical measurement of microscopic torques. J. Mod. Optics 48, 405–413 (2001).

    Article  Google Scholar 

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We thank the UK Engineering and Physical Sciences Research Council (EPSRC), the European Science Foundation SONS project NOMSAN and the European Commission 6th framework programme—NEST ADVENTURE Activity—through Project ATOM-3D (Contract No. 508952), for their support of this work. M. P. MacDonald acknowledges the support of an EPSRC Advanced Research Fellowship.

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Correspondence to Steven L. Neale.

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Neale, S., MacDonald, M., Dholakia, K. et al. All-optical control of microfluidic components using form birefringence. Nature Mater 4, 530–533 (2005).

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