29 June 2001 Taking light pressure serious: light as a quasimechanical microtool
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Proceedings Volume 4430, ROMOPTO 2000: Sixth Conference on Optics; (2001) https://doi.org/10.1117/12.432895
Event: ROMOPTO 2000: Sixth Conference on Optics, 2000, Bucharest, Romania
Light pressure may arise from absorption and can then be calculated as pressure equals intensity / vacuum velocity of light. Alternatively, it may result from scattering and is then called gradient force. In that case a quality factor Q has to be introduced, which has to be determined by calibration. Its numerical value is between 0.05 and 0.3. By coupling a NdYAG laser into a microscope with a high numerical aperture objective scattering light pressure can be used to move micrometer-sized dielectric objects. Such optical tweezers can be calibrated and have been used to measure forces needed to stretch individual DNA molecules, and to measure forces exerted by the motor proteins myosin, kinesin and dynein non-calibrated optical tweezers are used to handle individual DNA molecules after their coupling to micrometer-sized microbeads. Using enzymes which cut DNA molecules in a sequence specific fingerprint-like pattern, it is possible to analyze DNA on a single molecule basis.
© (2001) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Karl-Otto Greulich, Karl-Otto Greulich, Buerk Schaefer, Buerk Schaefer, Shamci Monajembashi, Shamci Monajembashi, "Taking light pressure serious: light as a quasimechanical microtool", Proc. SPIE 4430, ROMOPTO 2000: Sixth Conference on Optics, (29 June 2001); doi: 10.1117/12.432895; https://doi.org/10.1117/12.432895

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