Related Experiment Video
Updated: Jun 1, 2026
11:08
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Optomechanical coupling in a two-dimensional photonic crystal defect cavity.
E Gavartin1, R Braive, I Sagnes
1Ecole Polytechnique Fédérale de Lausanne, EPFL, 1015 Lausanne, Switzerland.
Physical Review Letters
|June 15, 2011
Summary
Researchers studied optomechanical properties in photonic crystal cavities. They measured high optical and mechanical mode coupling rates exceeding 80 kHz, demonstrating potential for advanced devices.
Area of Science:
- Optomechanics
- Photonics
- Materials Science
Background:
- Periodically structured materials exhibit coupled optical and mechanical modes.
- Photonic crystal defect cavities offer confined optical modes within small volumes.
Purpose of the Study:
- Investigate the optomechanical properties of a 2D suspended photonic crystal defect cavity.
- Experimentally measure the optomechanical vacuum coupling rate.
Main Methods:
- Fabrication and characterization of a 2D suspended photonic crystal defect cavity.
- Experimental observation of flexural and localized mechanical modes.
- Frequency calibration technique for measuring optomechanical coupling.
Main Results:
- Observed two families of mechanical modes: flexural and localized GHz-frequency modes.
- Directly measured optomechanical vacuum coupling rates.
- Achieved highest coupling rates exceeding 80 kHz.
Conclusions:
- Demonstrated strong optomechanical coupling in suspended photonic crystal cavities.
- Localized mechanical modes within the optical defect are significant.
- These structures show promise for optomechanical applications.
Related Concept Videos
01:26Imperfections in Crystal Structure: Stoichiometric Point Defects
Schottky defects arise when some lattice points in a crystal, such as those in NaCl, remain unoccupied, creating lattice vacancies without disturbing the overall electrical neutrality of the crystal. This defect is common in ionic crystals where the positive and negative ions are similar in size, as seen in sodium chloride and cesium chloride. The presence of Schottky defects enables the crystal to conduct electricity to a small extent through an ionic mechanism. Electric fields cause nearby...
01:25Imperfections in Crystal Structure: Point, Line and Plane Defects
A perfect crystal, in theory, has a uniform structure with the same unit cell and lattice points throughout. However, any deviation from this periodic arrangement is known as an imperfection or defect. These defects can be categorized into three types: point, line, and plane defects.Point defects occur when there is a deviation from the ideal due to missing atoms, displaced atoms, or additional atoms. These imperfections might occur due to imperfect packing during crystallization or because of...
01:28Standing Waves in a Cavity
A household microwave and lasers are examples of standing electromagnetic waves in a cavity. When two conducting metal plates are placed parallel at the nodal planes, it creates a cavity where standing waves are formed. The cavity between the two planes is analogous to a stretched string held at the points x = 0 and x = L. Here, the distance 'L' between the two planes must be an integer multiple of half of the wavelength. The wavelengths that satisfy this condition are given by:
01:29Imperfections in Crystal Structure: Non-Stoichiometric Defects
Non-stoichiometric defects refer to a type of defect in the crystal structure of a compound where the ratio of its constituent elements deviates from the ideal stoichiometric ratio. There are two main types of non-stoichiometric defects: metal excess defects and metal deficiency defects.Metal excess defects occur when there is a slight surplus of metal ions than what is required by the stoichiometric ratio of the compound. For example, heating a sodium chloride crystal in sodium vapor results...
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...