Abstract

We present a deterministic method to generate modified helical beams which create optical vortices with desired dark core intensity patterns in the far-field. The experiments are implemented and verified by a spatial light modulator (SLM), which imprints a phase function onto the incident wavefront of a TEM00 laser mode to transform the incident beam into a modified helical beam. The phase function can be calculated once a specific dark core shape of an optical vortex is required. The modified helical beam is exploited in optical manipulation with verification of its orbital angular momentum experimentally.

© 2005 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |

  1. A. Ashkin, J. M. Dziedzic, J. E. Bjorkholm, and S. Chu, �??Observation of a single-beam gradient force optical trap for dielectric particles,�?? Opt. Lett. 11, 288-290 (1986).
    [CrossRef] [PubMed]
  2. K. T. Gahagan and G. A. Swartzlander Jr., �??Optical vortex trapping of particles,�?? Opt. Lett. 21, 827-829 (1996).
    [CrossRef] [PubMed]
  3. H. He, N. R. Heckenberg, and H. Rubinsztein-Dunlop, �??Optical particle trapping with higher-order doughnut beams produced using high efficiency computer generated holograms,�?? J. Mod. Opt. 42, 217-223 (1995).
    [CrossRef]
  4. M. E. J. Friese, J. Enger, H. Rubinsztein-Dunlop, and N. R. Heckenberg, �??Optical angular-momentum transfer to trapped absorbing particles,�?? Phys. Rev. A 54, 1593-1596 (1996).
    [CrossRef] [PubMed]
  5. J. E. Curtis and D. G. Grier, �??Modulated optical vortices,�?? Opt. Lett. 28, 872-874 (2003).
    [CrossRef] [PubMed]
  6. D. W. Zhang and X.-C. Yuan, �??Optical doughnut for optical tweezers,�?? Opt. Lett. 28, 740-742 (2003).
    [CrossRef] [PubMed]
  7. W. M. Lee, X.-C. Yuan, and W. C. Cheong, �??Optical vortex beam shaping by use of highly efficient irregular spiral phase plates for optical micromanipulation,�?? Opt. Lett. 29, 1796-1798 (2004).
    [CrossRef] [PubMed]
  8. N. R. Heckenberg, R. McDuff, C. P. Smith, H. Rubinsztein-Dunlop, and M. J. Wegener, �??Laser beams with phase singularities,�?? Opt. Quantum Electron. 24, 951-962 (1992).
    [CrossRef]

J. Mod. Opt. (1)

H. He, N. R. Heckenberg, and H. Rubinsztein-Dunlop, �??Optical particle trapping with higher-order doughnut beams produced using high efficiency computer generated holograms,�?? J. Mod. Opt. 42, 217-223 (1995).
[CrossRef]

Opt. Lett. (5)

Opt. Quantum Electron. (1)

N. R. Heckenberg, R. McDuff, C. P. Smith, H. Rubinsztein-Dunlop, and M. J. Wegener, �??Laser beams with phase singularities,�?? Opt. Quantum Electron. 24, 951-962 (1992).
[CrossRef]

Phys. Rev. A (1)

M. E. J. Friese, J. Enger, H. Rubinsztein-Dunlop, and N. R. Heckenberg, �??Optical angular-momentum transfer to trapped absorbing particles,�?? Phys. Rev. A 54, 1593-1596 (1996).
[CrossRef] [PubMed]

Supplementary Material (1)

» Media 1: MPG (2346 KB)     

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (4)

Fig. 1.
Fig. 1.

Desired polygonal perimeter R(θ) of dark core

Fig. 2.
Fig. 2.

Far-field intensity distributions of modified helical beam with different b

Fig. 3.
Fig. 3.

Far-field intensity distribution of the modified helical beams with designated shapes of perimeter such as triangle, Greek cross, star and three letters (N, T, and U). The uppermost row shows the desired shapes of perimeter. The middle low shows the far-field distribution of corresponding modified helical beams through simulation. The bottommost is the experimentally observed far-field patterns. All patterns are designed with overall topological charge l=60.

Fig. 4.
Fig. 4.

Polystyrene spheres are trapped by modified optical vortex with triangle perimeter. Movie (2.5MB) shows eight polystyrene spheres moving along perimeter of triangle.

Equations (8)

Equations on this page are rendered with MathJax. Learn more.

R I ( θ ) = a I λ N A [ 1 + 1 b I d φ ( θ ) d θ ]
R ( θ ) = a λ N A [ 1 + 1 b d φ ( θ ) d θ ] = a b λ N A [ b + d φ ( θ ) d θ ]
R ( θ ) b + d φ ( θ ) d θ
R ( θ ) = 0 2 π R ( t ) d t 2 π ( l + b ) [ b + d φ ( θ ) d θ ]
φ ( θ ) = 2 π ( l + b ) 0 θ R ( t ) d t 0 2 π R ( t ) d t b θ
R ( θ ) = { r 1 r 2 sin θ 2 r 2 sin ( θ θ 2 ) r 1 sin θ for 0 θ < θ 2 r 2 r 3 sin ( θ 2 θ 3 ) r 3 sin ( θ θ 3 ) r 2 sin ( θ θ 2 ) for θ 2 θ < θ 3 r i r i + 1 sin ( θ i θ i + 1 ) r i + 1 sin ( θ θ i + 1 ) r i sin ( θ θ i ) for θ i θ < θ i + 1 , 2 i n 1 r n 1 r n sin ( θ n 1 θ n ) r n sin ( θ θ n ) r n 1 sin ( θ θ n 1 ) for θ n 1 θ < θ n r n r 1 sin θ n r 1 sin θ r n sin ( θ θ n ) for θ n θ < 2 π
φ ( θ ) = 2 π ( l + b ) I ( θ ) I total b θ
φ ( θ ) = 1.4 π l I ( θ ) I total 0.3 θ

Metrics