Kaleidoscope vortex lasers generated from astigmatic cavities with longitudinal-transverse coupling.

Area of Science:

• Optics and Photonics
• Laser Physics
• Quantum Optics

Background:

• Vortex beams, characterized by helical phase fronts, carry orbital angular momentum (OAM).
• Generating complex vortex beam structures, such as kaleidoscope vortex beams, is crucial for advanced optical applications.
• Existing methods for vortex beam generation can be complex or limited in tunability.

Purpose of the Study:

• To propose and demonstrate an efficient and robust method for generating kaleidoscope vortex beams.
• To investigate the formation mechanism of kaleidoscope vortex beams arising from mode superposition and longitudinal-transverse coupling.
• To achieve systematic control over the symmetry of generated kaleidoscope vortex beams.

Main Methods:

• Employing an astigmatic laser cavity with an additional external cylindrical lens.
• Utilizing the superposition of Laguerre-Gaussian modes within the laser cavity.
• Experimentally demonstrating the generation of kaleidoscope vortex beams with varying symmetry.

Main Results:

• Successful generation of kaleidoscope vortex beams with controllable symmetry.
• Observation of complex phase singularities resulting from mode superposition.
• Demonstration of the dependence of laser output power on cavity length.

Conclusions:

• The proposed method provides an efficient and robust way to generate kaleidoscope vortex beams.
• The technique allows for systematic control over beam symmetry and offers potential for creating high-order optical vortex beams.
• This approach may facilitate advancements in optical entanglement and related quantum information processing.