[2] [2] Allen L,Beijersbergen M W,Spreeuw R J C,et al. Orbital angular momentum of light and the transformation of Laguerre-Gaussian laser modes [J].Phys. Rev. A,1992,45: 8185-8189.

[3] [3] Molina-Terriza G,Torres J P,Torner L. Management of the angular momentum of light: preparation of photons in multidimensional vector states of angular momentum [J].Phys. Rev. Lett.,2002,88: 013601.

[4] [4] Torner L,Torres J,Carrasco S. Digital spiral imaging [J].Optics Express,2005,13(3): 873-881.

[5] [5] Neil A T,Mac Vicar I,Allen L,et al. Intrinsic and extrinsic nature of the orbital angular momentum of a light beam [J].Phys. Rev. Lett.,2002,88(5): 053601-4.

[6] [6] Parget M,Arlt J,Simpson N,et al. An experiment to observe the intensity and phase structure of Laguerre-Gaussian laser modes [J].Am. J. Phys.,1996,64: 77-82.

[7] [7] Beijersbergen M W,Coerwinkel R P C,Kristensen M,et al. Helical-wavefront laser beams produced with a spiral phaseplate [J].Opt. Commun.,1994,112: 321-327.

[8] [8] Heckenberg N R,McDuff R,Smith C P,et al. Generation of optical phase singularities by computer-generated holograms [J].Opt. Lett.,1992,17: 221-223.

[9] [9] Sueda K,Miyaji G,Miyanaga N,et al. Laguerre-Gaussian beam generated with a multilevel spiral phase plate for high intensity laser pulses [J].Optics Express,2004,12(15): 3548-3553.

[10] [10] McGloin D. Transfer of orbital angular momentum from a stressed fiber-optic waveguide to a light beam [J].Appl.Opt.,1998,37(3): 469-472.

[11] [11] Allen I,Beijersbergen M W,Spreeuw R J,et al. Orbital angular momentum of light and the transformation of Laguerre-Gaussian laser modes [J].Phy. Rev. A,1992,45(11): 8185-8189.

[12] [12] Barnet S M,Allen L. Orbital angular momentum and nonparaxial light beams [J].Opt. Commun.,1994,110:679-688.

[13] [13] O'Neill A T,Padgett M J. Axial and lateral trapping efficiency of Laguerre-Gaussian modes in inverted optical tweezers[J].Opt. Commun.,2000,193: 45-50.

[14] [14] Bouchal Z,Celechovsky R. Mixed vortex states of light as information carriers[J].New J. Phys.,2004,6: 131.

[15] [15] Celechovsky R,Boucha Z. Generation of variable mixed vortex fields by a single static hologram [J].Journal of Modern Optics,2006,53(4): 473-480.

[16] [16] Beijersbergen M W,Allen L,van der Veen HELO,et al. Astigmatic laser mode converters and transfer of orbital angular momentum [J].Opt. Commun.,1993,96: 123-132.

[17] [17] Brambilla M,Lugiato L A,Penna V,et al. Transverse laser patterns. I. Phase singularity crystals [J].Phys. Rev.A.,1991,43: 5090-5113.

[18] [18] Brambilla M,Lugiato L A,Penna V,et al. Transverse laser patterns. Ⅱ. Variational principle for pattern selection,spatial multistability,and laser hydrodynamics [J].Phys. Rev. A.,1991,43: 5114-5120.

[19] [19] Cullet P,Gil L,Rocca F. Optical vortices [J].Opt. Commun.,1989,73: 403-408.

[20] [20] Oppo G L,Gil L,D'Alessandro G,et al. Optical vortices in lasers [C].ECOOSA-90-Quantum-Optics,1991,191-194.

[21] [21] Guti érrez-Vega J C,Bandrées M A. Helmholtz-Gauss beams [J].J. Opt. Soc. Am. A,2005,22(2): 289-298.

[22] [22] Gibson G,Courtial J,Padgett M J. Free-space information transferusing light beams carrying orbital angular momentum [J].Optics Express,2004,12(22).

[24] [24] Durnin J. Exact solutions for nondiffracting beams. I. The scalar theory [J].J. Opt. Soc. Am. A,1987,4(4):651-654.

[25] [25] Durnin J,Micely J,Eberly J H. Diffraction-free beams [J].Phys. Rev. Lett.,1987,58(15): 1499-1501.

[26] [26] Wu Jingzhi. Encoding information as light's orbital angular momentum for optical communications [D].North University of China,2007.

[27] [27] McQueen C A,Arlt J,et al. An experiment to study a“nondiffracting”light beam [J].Am. J. Phys.,1999,67(10): 912-915.

[28] [28] Turubule G A,Robert sovb D A,Smith G M. et al. The generation of free-space Laguerre-Gaussian modes at millimet re-wave frequencies by use of a spiral phaseplate [J].Opt. Commun.,1996,127: 183-188.

[29] [29] Courtial J. Padgett M J. Performance of a cylindrical lens made converter for producing Laguerre-Gascssian laser modes [J].Opt. Commun.,1999,159: 13-18.