Rocking filter in a highly birefringent fiber for resonant coupling between different LP₁₁ modes and generation of...

Area of Science:

• Optics and Photonics
• Fiber Optics
• Waveguide Engineering

Background:

• Mode coupling in optical fibers is crucial for various photonic applications.
• Highly birefringent two-mode fibers offer unique properties for manipulating light polarization and spatial modes.
• Controlling resonant coupling between specific fiber modes remains a challenge.

Purpose of the Study:

• To introduce a novel rocking filter design for highly birefringent two-mode fibers.
• To demonstrate resonant coupling between different modes within the LP11 group.
• To explore the generation of specific optical beam profiles using the developed filter.

Main Methods:

• Simulations of light propagation in a rocking filter integrated into a highly birefringent two-mode fiber.
• Experimental validation of the filter's performance.
• Characterization of generated optical beams (TE01, TM01, HE21).

Main Results:

• The rocking filter enables resonant coupling between orthogonally polarized LP11 modes with the same spatial structure.
• Coupling is also achieved between modes of the same polarization but orthogonal spatial distributions.
• The filter successfully generates pure TE01, TM01, and HE21 beams, as well as their coherent superpositions.

Conclusions:

• Rocking filters are effective tools for achieving controlled mode coupling in highly birefringent two-mode fibers.
• This technology facilitates the generation of tailored optical beams for advanced photonic applications.
• The demonstrated capabilities open new avenues for beam shaping and mode manipulation in fiber optics.