Coherent detector for the non-separability measurement of vectorial structured light

Area of Science:

• Optical physics
• Free-space optical communication

Background:

• Atmospheric turbulence degrades free-space optical communication by distorting light wavefronts.
• The non-separability of vectorial structured light is invariant to atmospheric turbulence, offering a path for robust communication.

Purpose of the Study:

• To develop an efficient and compact method for detecting the non-separability of vectorial structured light for turbulence-resilient optical communications.
• To overcome limitations of existing detection schemes that use bulky components and lack single-shot capability.

Main Methods:

• Proposed and demonstrated a coherent detector utilizing off-axis digital holography.
• Employed digital decomposition of spatial modes for characterization.
• Enabled detection of mode-resolved non-separability contributions.

Main Results:

• Successfully characterized the non-separability of vectorial structured light.
• Demonstrated a compact and efficient detection scheme.
• Overcame limitations of traditional spatial light modulator (SLM) or digital micromirror device (DMD) based methods.

Conclusions:

• The developed coherent detector provides a novel approach for turbulence-resilient optical communications.
• This method enables efficient measurement of non-separability, crucial for encoding information robustly.
• Paves the way for new insights into non-separability measurement and optical communication systems.