Abstract This paper introduces Lorentz beams to describe certain laser sources that produce highly divergent fields. The fractional Fourier transform (FRFT) is applied to treat the propagation of Lorentz beams. Based on the definition of convolution and the convolution theorem of the Fourier transform, an analytical expression for a Lorentz beam passing through a FRFT system has been derived. By using the derived formula, the properties of a Lorentz beam in the FRFT plane are illustrated numerically.
Received: 05 November 2008
Revised: 02 December 2008
Accepted manuscript online:
PACS:
42.60.Jf
(Beam characteristics: profile, intensity, and power; spatial pattern formation)
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