Infrared Optical Vortices Generation with Holographic Optical Elements Recorded in Bayfol HX200 Photopolymer

Infrared optical vortices are used in the field of optical communications at wavelengths around 1550 nm. A versatile method to generate them is with a Spatial Light Modulator (SLM); however, they are expensive devices and cannot be easily integrated into compact systems, as opposed to Holographic Optical Elements (HOEs), which are lightweight, smaller and thinner, and easier to align and combine with other optical systems. In this work, volume transmission HOEs have been recorded in a commercial photopolymer, Bayfol HX200, by exposing it to the interference pattern obtained with an optical vortex (obtained with an SLM) and a plane wave in the visible range. When illuminated with a plane wave at 1534 nm, the diffracted beam carried an optical vortex. An experimental efficiency of approximately 45% at that wavelength has been obtained, proving the viability of the method.