Picometer Scale Photothermal Tuning of Plasmonic Nanocavities and Interfacial Processes

Area of Science:

• Nanophotonics
• Plasmonics
• Materials Science

Background:

• Precise tuning of plasmon resonances is crucial for nanophotonic and sensing technologies.
• Existing methods often rely on static inorganic spacers, limiting real-time tunability.

Purpose of the Study:

• To demonstrate picometer-level tunability of plasmon resonances in nanorod-on-mirror nanocavities.
• To utilize the photothermal effect in polyelectrolyte (PE) layers for dynamic nanocavity adjustment.

Main Methods:

• Employing polyelectrolyte (PE) layers as dielectric spacers in nanorod-on-mirror nanocavities.
• Exploiting the photothermal effect induced by laser illumination to alter PE spacer thickness and phase.
• Investigating the influence of laser power and initial spacer thickness on plasmon resonance shifts.

Main Results:

• Achieved picometer-level tunability of plasmon resonances.
• Demonstrated real-time adjustment of nanocavity properties via photothermal effects in PE spacers.
• Observed shifts in plasmon resonances due to laser-induced PE spacer thickness reduction and phase transitions.

Conclusions:

• Polyelectrolyte spacers offer a dynamic alternative to inorganic materials for tuning plasmon resonances.
• This precise tuning capability opens avenues for exploring advanced photophysical processes and enhancing sensing signals.