Aperiodic nanoplasmonic devices for directional colour filtering and sensing

Area of Science:

• Photonics and Plasmonics
• Optical Engineering
• Materials Science

Background:

• Periodic structures are widely used for tunable optical devices like filters and spectrometers.
• However, periodic designs have limitations in achieving simultaneous enhancements in performance and functionality.
• Passive plasmonic devices at optical frequencies can benefit from novel architectural approaches.

Purpose of the Study:

• To explore aperiodic architectures for enhancing passive plasmonic devices.
• To design devices with flexible, multi-spectral optical responses beyond the capabilities of periodic structures.
• To demonstrate a simple and efficient route for creating advanced optical functionalities.

Main Methods:

• Utilized a first-order interference model for plasmon-light interactions.
• Designed and experimentally implemented aperiodic plasmonic structures.
• Investigated the optical response of devices concerning spectral and angular tunability.

Main Results:

• Demonstrated aperiodic devices with flexible, multi-spectral optical responses.
• Achieved ultra-compact directional light-filters and color-sorters.
• Exhibited high contrast and low crosstalk in spectral or spatial responses.

Conclusions:

• Aperiodic plasmonic systems offer a route to enhanced optical device performance and functionality.
• These devices enable tailored spectral and angular responses not possible with periodic designs.
• Promising applications include solar energy, optical multiplexing, and integrated sensing.