A radially polarized beam with an annular intensity pattern was generated through a second-harmonic-generation process by focusing an azimuthally polarized Ti:sapphire pulsed laser beam to a c-cut β-barium borate (BBO) crystal. The annular intensity pattern of the second-harmonic wave had a nearly sixfold symmetry as a result of the nonlinear susceptibility tensor of the BBO crystal. The width of the annulus was as narrow as less than 1/40th of its radius.
© 2009 Optical Society of America
Original Manuscript: July 1, 2009
Revised Manuscript: September 2, 2009
Manuscript Accepted: September 9, 2009
Published: October 9, 2009
Shunichi Sato and Yuichi Kozawa, "Radially polarized annular beam generated through a second-harmonic-generation process," Opt. Lett. 34, 3166-3168 (2009)