Dholakia, K.Lee, W. M.2025-12-312025-12-3197801237429021049-250XORCID:/0000-0002-3912-6095/work/162948688https://hdl.handle.net/1885/733797514Optical micromanipulation is a powerful and versatile technique based upon the light-matter interaction. Whilst the forces exerted by optical traps are naturally very small, they are sufficient to realize non-invasive mechanical control over mesoscopic particles within atomic, biological and colloidal systems. The inherent compatibility with modern microscopy enhances the reconfigurability of the trap while the accuracy achieved in a calibrated optical trap presents itself as a quantitative force probe. Thus forces can be applied in a controlled manner to biological systems including cells and molecular motors and processes measured with high precision. The impact is not limited to biology. Optical traps have provided seminal studies in colloidal and optical physics including the phase dynamics of thermodynamic systems, Brownian diffusion, aspects of microfluidics, and fundamental issues related to optical angular momentum. This article aims to focus upon the emergent theme of optical trappingOptical trapping with structured light fields. By structured light fields we refer to the generation of multiple arrays of traps and the use of specialist light fields such as Laguerre-Gaussian beams and Bessel beams. Structured light fields are making a major impact on optical trappingOptical trapping and on subsequent applications including those in biomedicine.The authors would like to thank the UK Science and Engineering Research Council for funding and Michael Mazilu, Tomas Cizmar, Joerg Baumgartl and David Stevenson for proof reading and useful comments.77enBeam opticsBiological fluid dynamicsBiomedical engineeringBiophysical techniques (research methods)Brownian motionColloidal systemsComplex fluids and colloidal systemsDynamics and kinematics of a particle and a system of particlesFluctuation phenomena, random processes, noise, and Brownian motionFluid mechanics and rheologyFourier opticsGeometrical opticsholographic gratingsHolographic optical elementsHolographyLaser applicationsLasersMechanical effects of light on material media, microstructures and particlesMicromanipulation of biological structuresNanotechnologies-applicationsOptical angular momentum and its quantum aspectsOptical instruments and equipmentOptical methodsOptical microscopyOptical trapping (see also 42.50.Wk Mechanical effects of light on material media, microstructure and particles in optics)Optoelectronic device characterization, design, and modelingParticle beam profile, beam intensityParticle beam transportrheo-opticsSelf-organized systemsSingle-molecule techniques (see also 82.37.Rs Single molecule manipulation of proteins and other biological molecules in physical chemistry)Spectroscopic and microscopic techniques in biophysics and medical physicsViscosity measurementsWave optics200810.1016/S1049-250X(08)00015-355049119109