posted on 2023-12-12, 06:44authored byAndrey Okhrimchuk, Vladislav Likhov, Sergei Vasiliev, Grigory Alagashev
Azimuthally segmented helical-ring-core waveguides (HRCW) were fabricated in silica glass by direct laser writing. Triple-segmented waveguides provided single-mode or few-mode light guidance depending on the core diameter. Bragg resonance reflection of light carrying Orbital Angular Momentum (OAM) was registered confirming the generalized angular phase matching condition, which considers azimuthally segmented structure of the waveguides.