Digital generation of partially coherent vortex beams

Area of Science:

• Optics and Photonics
• Quantum Optics
• Beam Shaping

Background:

• Partially coherent vortex beams are crucial for applications in optical manipulation and communication.
• Generating these beams with controlled orbital angular momentum (OAM) and coherence properties presents experimental challenges.

Purpose of the Study:

• To introduce a novel, versatile technique for generating partially coherent vortex beams with arbitrary azimuthal indices.
• To demonstrate the ability to control coherence length and OAM content digitally.
• To experimentally validate the generated beams using a wavefront folding interferometer.

Main Methods:

• Utilizing a spatial light modulator (SLM) to digitally simulate the randomness of broadband light passing through a spiral phase plate.
• Generating partially coherent vortex beams with varying coherence lengths and OAM.
• Employing a wavefront folding interferometer to measure the cross-correlation function of the generated beams.

Main Results:

• Successful generation of partially coherent vortex beams with controllable azimuthal indices.
• Demonstration of tunable coherence lengths and OAM content without mechanical components.
• Experimental results for the cross-correlation function showed excellent agreement with theoretical predictions.

Conclusions:

• The proposed technique offers a flexible and robust method for creating tailored partially coherent vortex beams.
• Digital simulation on an SLM provides an efficient alternative to traditional optical setups for beam generation.
• This method opens possibilities for advanced applications in optical physics and engineering.