Laser-optical trap

C. Mio, T. Gong, A. Terray and D.W.M. Marr, Design of a scaiming laser optical trap for multiparticle manipulation, Review of Scientific Instruments, 71(5), 2196-2200 (2000). 

Entropic and Enthalpic Elasticity. In recent years, SFM approaches and complementary force-sensing approaches, such as biomembrane probe and laser optical trap techniques, have been perfected to an extent that the study of individual (bio)macromolecules have become feasible as routine experiments in many... 

Movements of single myosin molecules along an actin filament can be measured by means of an optical trap consisting of laser beams focused on polystyrene beads attached to die ends of actin molecules. (Adapted from Finer et at., 1994. Nature 368 113- 119. See also Block, 1995. Nature 378 132 133.)... 

Figure 7.3 shows the two-beam photon-force measurement system using a coaxial illumination photon force measurement system. Two microparticles dispersed in a liquid are optically trapped by two focused near-infrared beams ( 1 pm spot size) of a CW Nd YAG laser under an optical microscope (1064 nm, 1.2 MWcm , lOOX oil-immersion objective, NA = 1.4). The particles are positioned sufficiently far from the surface of a glass slide in order to neglect the interaction between the particles and the substrate. Green and red beams from a green LD laser (532 nm, 21 kWcm ) and a He-Ne laser (632.8 nm, 21 kW cm ) are introduced coaxially into the microscope and slightly focused onto each microparticle as an illumination light (the irradiated area was about 3 pm in diameter). The sizes of the illumination areas for the green and red beams are almost the same as the diameter of the microparticles (see Figure 7.4). The back scattered light from the surface of each microparticle is...

The WGM laser mode structure is determined by the droplet size and shape (which can be influenced by optical trapping forces26), laser polarization, and dye concentration. ... 

Ashkin, A., Optical trapping and manipulation of neutral particles using lasers, Proc. Natl Acad. Sci. USA 1997, 94, 4853 4860... 

Ashkin, A. Dziedzic, J. M. Yamane, T., Optical trapping and manipulation of single cells using infrared laser beams, Nature 1987, 330, 769 771... 

Tadir, Y., Wright, W.H., Vafa, O., Ord, T., Asch, R.H., and Bems, M.W., Force generated by human sperm correlated to velocity and determined using a laser generated optical trap, Fertil. Steril., 53, 1990, 944-947. 

Bems, M. W., Aist, J. R., Wright, W. H., and Liang, H. (1992) Optical trapping in animal and fungal cells using a tunable, near-infrared titanium-sapphire laser. Exp. Cell Res. 198,375-378. 

Malmqvist, L., and Hertz, H. M., 1995. Second-harmonic generation in optically trapped nonlinear particles with pulsed lasers. Appl. Opt. 34 3392-97. 

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