Related Experiment Video
Updated: Jun 14, 2026
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Optomechanics with surface-acoustic-wave whispering-gallery modes.
A B Matsko1, A A Savchenkov, V S Ilchenko
1OEwaves Inc., 2555 East Colorado Boulevard, Suite 400, Pasadena, California 91107, USA.
Physical Review Letters
|April 7, 2010
Summary
Surface acoustic waves (SAW) generate unique whispering-gallery modes (WGM) in optical resonators. This enables efficient, controllable optomechanical interactions for advanced sensor applications.
Area of Science:
- Optomechanics
- Acoustic-optic devices
- Nanophotonics
Background:
- Whispering-gallery mode (WGM) resonators are crucial for photonics.
- Surface acoustic waves (SAW) typically generate bulk acoustic WGMs.
- Controlling optomechanical interactions in micro-resonators is a key challenge.
Purpose of the Study:
- To demonstrate a novel SAW-induced WGM in an optical resonator.
- To achieve externally controllable, triply resonant optomechanical coupling.
- To explore applications of this interaction in sensor technology.
Main Methods:
- Utilizing an optical dielectric WGM resonator.
- Generating a surface acoustic wave (SAW) to create a distinct WGM.
- Establishing optomechanical interaction between two optical WGMs and the SAW WGM.
Main Results:
- A high-Q, ultrasmall-volume SAW-induced WGM was created.
- Efficient, externally controllable triply resonant optomechanical interaction was realized.
- The system shows potential for diverse sensor applications.
Conclusions:
- SAW-induced WGMs offer a new pathway for optomechanical systems.
- This approach enables precise control over light-sound interactions.
- The developed optomechanical system is promising for next-generation sensors.
Related Concept Videos
01:04Modes of Standing Waves: II
The starting point for expressing the modes of standing waves is understanding the boundary conditions that the waves must follow. The boundary conditions are derived from the physical understanding of how the standing waves are sustained, that is, how the vibrating particles of the medium behave at the boundaries imposed on them.
For a tube open at one end and closed at the other filled with air, the modes are such that there is always an antinode at the open end and a node at the closed end.
For a tube open at one end and closed at the other filled with air, the modes are such that there is always an antinode at the open end and a node at the closed end.
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:
01:03Modes of Standing Waves - I
A close look at earthquakes provides evidence for the conditions appropriate for resonance, standing waves, and constructive and destructive interference. A building may vibrate for several seconds with a driving frequency matching the building's natural frequency of vibration; this produces a resonance that results in one building collapsing while the neighboring buildings do not. Often, buildings of a certain height are devastated, while other taller buildings remain intact. This phenomenon...
00:53Sound Waves: Interference
Sound waves can be modeled either as longitudinal waves, wherein the molecules of the medium oscillate around an equilibrium position, or as pressure waves. When two identical waves from the same source superimpose on each other, the combination of two crests or two troughs results in amplitude reinforcement known as constructive interference. If two identical waves, that are initially in phase, become out of phase because of different path lengths, the combination of crests with troughs...
01:14Sound Waves: Resonance
Resonance is produced depending on the boundary conditions imposed on a wave. Resonance can be produced in a string under tension with symmetrical boundary conditions (i.e., has a node at each end). A node is defined as a fixed point where the string does not move. The symmetrical boundary conditions result in some frequencies resonating and producing standing waves, while other frequencies interfere destructively. Sound waves can resonate in a hollow tube, and the frequencies of the sound...
01:01Sound Waves
Sound waves can be thought of as fluctuations in the pressure of a medium through which they propagate. Since the pressure also makes the medium's particles vibrate along its direction of motion, the waves can be modeled as the displacement of the medium's particles from their mean position.
Sound waves are longitudinal in most fluids because fluids cannot sustain any lateral pressure. In solids, however, shear forces help in propagating the disturbance in the lateral direction as well. Hence,...
Sound waves are longitudinal in most fluids because fluids cannot sustain any lateral pressure. In solids, however, shear forces help in propagating the disturbance in the lateral direction as well. Hence,...