Dielectric metasurfaces for next-generation optical biosensing: a comparison with plasmonic sensing

Area of Science:

• Nanophotonics
• Biosensing
• Metasurface Technology

Background:

• Plasmonic nanophotonic biosensors have been extensively studied.
• Dielectric metasurfaces offer an alternative platform based on Mie resonance.
• Plasmonic platforms face limitations due to photothermal effects, impacting biosensing performance.

Purpose of the Study:

• To review high-Q resonances in dielectric metasurfaces tailored by meta-atom design.
• To compare dielectric and plasmonic metasurfaces for refractometric, surface-enhanced, and chiral sensing.
• To highlight imaging-based and spectrometer-less biosensing modalities enabled by dielectric metasurfaces.

Main Methods:

• Review of high-Q resonances based on physical phenomena and meta-atom geometric designs.
• Comparison of dielectric and plasmonic metasurfaces in various sensing applications.
• Highlighting advanced biosensing techniques like hyperspectral imaging and single-wavelength barcoding.

Main Results:

• Dielectric metasurfaces provide comparable sensitivity to plasmonic platforms with superior resonance bandwidth, Q factor, and figure-of-merit.
• Dielectric metasurfaces overcome ohmic loss and heating issues, leading to improved repeatability, stability, and biocompatibility.
• Imaging-based and spectrometer-less biosensing modalities offer new possibilities for diagnostics and real-time monitoring.

Conclusions:

• Dielectric metasurfaces represent a significant advancement in optical biosensing.
• Future research directions include hyperspectral imaging and integrated sensing/output functionalities.
• Development towards next-generation ultra-sensitive, portable, and scalable biosensing applications is promising.