Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1538355 | Optics Communications | 2010 | 8 Pages |
We present a straightforward method to transform a spatially Gaussian femtosecond laser beam into a flat-top shaped beam. The proposed technique takes advantage of a nonlinear phase induced in positive Kerr medium followed by a simple optical system. The variation of the refractive index with the laser intensity creates a phase plate which induces changes in the beam profile after propagation; flat-top and doughnut profiles are observed. The shaping conditions are computed numerically and confirmed experimentally. The method does not introduce energy losses. The device is very simple, self-regulated, flexible and does not need a manufactured phase plate or precise alignment. This method can be useful for light-matter interaction and laser machining.