Abstract

High-order ring-shaped laser modes are attractive for applications such as laser micromachining and optical particle trapping due to their increased transverse intensity gradients compared to a fundamental Gaussian mode of the same size. In the case of micromachining, the steeper intensity profile of a single high-order ring-mode will yield a “sharper” cutting profile, while presenting a cutting face that is spatially identical for all cutting directions. The peak of the intensity gradient for a ring-shaped Laguerre-Gaussian (LG_0n) mode, when focussed to a given beam size, increases dramatically with increasing azimuthal mode order, n, so efficient high-order LG mode generation at high powers is very desirable.

© 2015 IEEE