Affiliation:
1. University of Naples Federico II
2. University of the Witwatersrand
Abstract
The use of nonlinear optics for the creation, control, and detection of structured light has gained prominence of late, but it is plagued by low efficiency and variable modal purity. Here, we show how to optimize the efficiency and modal purity in the nonlinear conversion of structured light modes. Using difference frequency generation of orbital angular momentum carrying Laguerre–Gaussian modes as an example, we achieved more than a 40% rise in efficiency while maintaining the modal purity above 90% compared to conventional methods. To demonstrate the versatility of our approach, we show the frequency conversion of perfect vortex beams up to ℓ=40 in a topological charge, achieving a new state of the art. We believe this theoretical treatment will facilitate our work’s translation to other modal forms and nonlinear processes.
Funder
National Research Foundation
Subject
Atomic and Molecular Physics, and Optics,Statistical and Nonlinear Physics