Optimized nanospherical layered alternating metal-dielectric probes for optical sensing

Area of Science:

• Nanotechnology
• Optical Physics
• Materials Science

Background:

• Multishell nanospheres, termed layered alternating metal-dielectric probes (LAMPs), are emerging as advanced tools for optical molecular imaging.
• These structures offer potential for enhanced sensitivity and multiplexing capabilities.

Purpose of the Study:

• To theoretically demonstrate the tunability of interplasmonic coupling and spectral responses in LAMPs.
• To explore the impact of layer thickness selection on LAMP performance.
• To design application-specific LAMPs through rational selection of material and dimensions.

Main Methods:

• Utilized layered Mie theory to calculate near- and far-field characteristics of nanospheres.
• Employed a genetic algorithm for optimizing layer thicknesses.
• Investigated gold-silica, silver-silica, and copper-silica LAMPs.

Main Results:

• Demonstrated that spectral responses of LAMPs can be precisely tuned by adjusting layer thicknesses.
• Showcased optical tunability enabling the design of probes specific to excitation wavelengths and sizes.
• Observed increased tunability with a higher number of layers, allowing for longer wavelength resonances.

Conclusions:

• Rational design of layer thicknesses provides significant optical tunability in LAMPs.
• This tunability allows for the creation of customized probes for diverse optical molecular imaging applications.
• The findings pave the way for developing next-generation imaging probes with tailored spectral properties.