On-chip noninterference angular momentum multiplexing of broadband light.

Area of Science:

• Optics and Photonics
• Nanotechnology
• Information Technology

Background:

• Angular momentum division is a key multiplexing method for high-capacity optical information.
• Traditional methods using bulky elements limit on-chip integration.
• Interference-based retrieval methods are not scalable for miniaturized devices.

Purpose of the Study:

• To demonstrate a novel noninterference angular momentum multiplexing technique.
• To overcome the limitations of bulky elements in current optical information retrieval.
• To enable on-chip parallel multiplexing for ultrahigh-capacity nanophotonic devices.

Main Methods:

• Utilized a mode-sorting nanoring aperture with a chip-scale footprint (4.2 µm x 4.2 µm).
• Leveraged nanoring slits for efficient outcoupling of tightly confined plasmonic modes.
• Employed nonresonant mode-sorting for high sensitivity and scalability.

Main Results:

• Successfully demonstrated noninterference angular momentum multiplexing.
• Achieved on-chip parallel multiplexing over a 150 nm bandwidth in the visible range.
• The nanoring aperture exhibited distinctive outcoupling efficiency on plasmonic modes.

Conclusions:

• The developed method offers a pathway to ultrahigh-capacity and miniaturized nanophotonic devices.
• Noninterference approach removes fundamental limits imposed by bulky interference elements.
• Scalability and sensitivity pave the way for practical on-chip angular momentum division.