Title :
Beam magnification and the efficiency of optical trapping with 790-nm AlGaAs laser diodes
Author :
Escandon, G.J. ; Liu, Y. ; Sonek, G.J. ; Berns, M.W.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Irvine, CA, USA
fDate :
5/1/1994 12:00:00 AM
Abstract :
The efficiency of dielectric particle confinement with 790 nm AlGaAs laser diode optical traps is investigated as a function of beam magnification and polarization state. When an anamorphic prism pair is used to correct for diode beam ellipticity, trapping efficiencies of nearly 0.37 are achieved with a magnification factor of 3×, laser powers of 4-18 mW, and an overfilled microscope objective entrance aperture. Results are compared for diodes having small (8 μm) and large (57 μm) astigmatisms, but comparable far-field divergence angles.
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; laser beam effects; light polarisation; radiation pressure; semiconductor lasers; 4 to 18 mW; 790 nm; AlGaAs; AlGaAs laser diodes; anamorphic prism pair; astigmatisms; beam magnification; dielectric particle confinement; diode beam ellipticity; far-field divergence angles; laser diode optical traps; laser powers; magnification factor; optical trapping; overfilled microscope objective entrance aperture; polarization state; trapping efficiencies; Apertures; Charge carrier processes; Dielectrics; Diode lasers; Laser beams; Microscopy; Optical polarization; Particle beams; Power lasers; Vision defects;
Journal_Title :
Photonics Technology Letters, IEEE
