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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Stability of optical resonators with an active medium.
Applied Optics
|February 6, 2010
Summary
Gaussian modes in optical resonators are stable when gain is highest on the axis. Off-axis gain leads to unstable modes, diverging to infinite spot size, impacting resonator performance.
Area of Science:
- * Optical physics and resonator design.
- * Laser engineering and mode stability analysis.
Background:
- * Investigating the stability of Gaussian modes in optical resonators with large apertures is crucial for laser performance.
- * A discrepancy in previous research on mode stability necessitates clarification.
Purpose of the Study:
- * To analyze the stability of Gaussian modes in optical resonators with gain and index profiles.
- * To resolve conflicting results from prior investigations on resonator mode stability.
Main Methods:
- * Theoretical examination of Gaussian mode stability in optical resonators.
- * Analysis of gain and index profiles within the resonator medium.
- * Evaluation of mode behavior under varying gain distribution.
Main Results:
- * Resonator modes are stable when the gain profile is highest on the resonator axis.
- * If gain increases away from the axis, calculated Gaussian eigenmodes become unstable.
- * Unstable modes diverge to an infinite spot size with slight parameter deviations.
Conclusions:
- * Gain distribution is a critical factor determining Gaussian mode stability in optical resonators.
- * On-axis gain is essential for maintaining stable Gaussian modes.
- * Off-axis gain profiles lead to inherent instability in resonator modes.
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