Deformable two-dimensional photonic crystal slab for cavity optomechanics

Area of Science:

• Optics and Photonics
• Mechanical Engineering
• Quantum Technology

Background:

• Cavity optomechanics studies the interaction between light and mechanical motion.
• High-quality resonators are crucial for observing subtle optomechanical effects.
• Existing mirror technologies may have limitations in mass or optical performance.

Purpose of the Study:

• To design and characterize photonic crystal suspended membranes for cavity optomechanics.
• To optimize both optical and mechanical properties for enhanced performance.
• To enable the use of these structures as deformable end mirrors in Fabry-Perot cavities.

Main Methods:

• Fabrication of photonic crystal suspended membranes with a 2D square lattice of holes.
• Optical characterization of reflectivity at normal incidence (1064 nm).
• Mechanical characterization of vibration modes in the megahertz range and associated quality factors.

Main Results:

• Achieved reflectivity as high as 95% at 1064 nm.
• Resonators sustain vibration modes in the megahertz range.
• Quality factors in the thousands were measured for the mechanical modes.
• The membranes possess very low mass.

Conclusions:

• The designed photonic crystal membranes possess optimized optical and mechanical properties.
• These membranes are suitable for use as low-mass, deformable end mirrors.
• They pave the way for investigating cavity optomechanical effects with improved sensitivity.