Optical Angular Momentum Beam Generation Using Coherent Beam Combination

Abstract

(1) Background: The significant progress observed over the last two decades in coherent beam combining (CBC) technology has mainly focused on its applications in high-energy physics and laser weapons. This work provides insight into the basic principles of CBC and the search for an alternative, namely optical angular momentum (OAM) generation using CBC. (2) Methods: A semi-analytical model based on the paraxial wave equation was explored, generating OAM-CBC beams by manipulating the tilts and phases of the CBC (T&P-CBC) of hexagonal architecture. (3) Results: The specially arranged T&P-CBC shows typical properties of OAM, such as annular profiles for the zero diffraction order and 1st-order replicas in the far field and correlation coefficients of 1% between different OAM-CBC fields. (4) Conclusions: The differences between classical OAM beams and OAM-CBC are substantial due to hexagonal lattice properties. Moreover, applications in free space optical communications are feasible as T&P CBC fulfills the main conditions and requirements for OAM generation.

Keywords

• laser beams
• coherent beam combining
• optical angular momentum
• vortex beams
• free-space optical communications