Characteristics of fork-shaped fringes formed by off-axis interference of two vortex beams
Jingbo Ma, Peng Li, Ziheng Zhou, Yuzong Gu
Abstract
Fork-shaped fringes are formed for off-axis interference between two oblique-incident vortex beams. New formulas considering various parameters [such as the angles between two vortex beams and their topological charges (TCs)] are established to describe all kinds of fork-shaped fringes. An improved Mach-Zehnder interferometer is employed to investigate these interference fringes. Experimental measurements are consistent with numerical simulations by using our formulas. Our results broaden the understanding of the off-axis interference between two vortex beams, and can be applied to detect the TCs' sign and value of an unknown vortex beam, especially large-value TCs.
Topics & Concepts
Interference (communication)VortexOpticsPhysicsInterferometryOblique caseSign (mathematics)Mach–Zehnder interferometerBeam (structure)Channel (broadcasting)MechanicsTelecommunicationsMathematicsEngineeringPhilosophyMathematical analysisLinguisticsOrbital Angular Momentum in OpticsPlasmonic and Surface Plasmon ResearchOptical Coatings and Gratings