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Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
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A one-dimensional optomechanical crystal with a complete phononic band gap
J Gomis-Bresco1, D Navarro-Urrios2, M Oudich3
11] ICN2-Institut Catala de Nanociencia i Nanotecnologia, Campus UAB, 08193 Barcelona, Spain [2].
Nature Communications
|July 22, 2014
Summary
This study demonstrates a novel 1D optomechanical crystal with a complete phononic bandgap, enabling high-quality gigahertz acoustic modes. This design minimizes acoustic leakage and fabrication imperfections for enhanced device performance.
Area of Science:
- Optomechanics
- Nanoscale physics
- Solid-state physics
Background:
- Cavity optomechanics integrates optical and mechanical waves at the nanoscale.
- Optomechanical (OM) crystals on semiconductor slabs allow on-chip integration and manipulation of OM elements.
- Existing OM crystal designs often lack a complete phononic bandgap, limiting phonon lifetimes due to acoustic leakage.
Purpose of the Study:
- To demonstrate the excitation of acoustic modes within a complete phononic bandgap in a 1D OM crystal.
- To design OM crystal structures that minimize acoustic leakage and fabrication imperfections.
- To achieve gigahertz acoustic modes with high mechanical quality factors.
Main Methods:
- Design and fabrication of a one-dimensional optomechanical crystal.
- Engineering the crystal structure to exhibit a complete phononic bandgap for acoustic modes at 4 GHz.
- Characterization of acoustic modes within the bandgap for high mechanical Q-factors.
Main Results:
- Demonstrated excitation of acoustic modes within a complete phononic bandgap at 4 GHz.
- The designed OM crystal exhibits a full phononic bandgap, minimizing acoustic leakage.
- Engineered modes possess high mechanical Q-factors and are robust against fabrication imperfections.
Conclusions:
- The developed 1D OM crystal design successfully creates a complete phononic bandgap for gigahertz acoustic modes.
- This approach enhances phonon lifetimes and device robustness, paving the way for advanced optomechanical applications.
- The findings are crucial for coherent phonon manipulation and integrated optomechanical circuits.
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