Picosecond optomechanical oscillations in metal-polymer microcavities

Area of Science:

• Optomechanics
• Materials Science
• Acoustics

Background:

• Fabry-Perot microcavities are crucial optical resonators.
• Metallic mirrors offer strong optical absorption, while polymers provide elasticity and processability.
• Understanding mechanical vibrations in such hybrid structures is key for device development.

Purpose of the Study:

• To experimentally investigate mechanical vibrations in metallic-mirror polymer microcavities.
• To analyze the dynamics and origin of acoustic waves within these structures.
• To explore the potential of these hybrid materials for novel optomechanical devices.

Main Methods:

• Broadband pump-probe spectroscopy was employed to study mechanical vibrations.
• Planar Fabry-Perot microcavities with metallic mirrors and polymer spacers were fabricated.
• Analysis focused on spectral oscillations in cavity transmission.

Main Results:

• Picosecond timescale acoustic waves were observed, causing spectral oscillations.
• Vibrations were initiated at the metal mirrors.
• The temporal dynamics of oscillations matched the elastic modes of the polymer layer, confirming momentum transfer.

Conclusions:

• Mechanical momentum is effectively transferred within metal-polymer microcavity structures.
• These hybrid structures combine desirable optical and mechanical properties.
• The findings open avenues for developing new optomechanical devices leveraging metal-polymer interfaces.