Integration of orbital angular momentum in optical coherence tomography

Optical Coherence Tomography (OCT) is a widely used non-invasive imaging technique, particularly in ophthalmology, offering high-resolution cross-sectional images of biological tissues. However, traditional OCT faces limitations in penetration depth and sensitivity, especially in highly scattering tissues. This work explores the integration of orbital angular momentum (OAM) with classical OCT. We demonstrate the generation of high-purity OAM modes in an OCT-compatible setup. The purity of these modes was evaluated through phase retrieval and OAM spectrum decomposition. While the use of a broadband source results in a reduction of mode purity, the dominant component remains the correctly generated OAM mode. Our preliminary results suggest the potential for using OAM as an additional degree of freedom in OCT, with applications for noise filtering and resolution enhancement. Furthermore, this approach could be extended to quantum OCT, where OAM entanglement is naturally integrated into the spontaneous parametric down-conversion (SPDC) process for photon generation.