Related Experiment Video
Updated: Nov 5, 2025
12:21
Stimulated Stokes and Antistokes Raman Scattering in Microspherical Whispering Gallery Mode Resonators
Published on: April 4, 2016
11.4K
Fine structure of second-harmonic resonances in χ(2) optical microresonators
Optics Express
|May 14, 2021
Summary
This study models second-harmonic generation in whispering gallery resonators (WGRs) with frequency detunings. The model accurately predicts resonance distortions and efficiency, validated by lithium niobate WGR experiments.
Area of Science:
- Nonlinear optics
- Photonics
- Resonator physics
Background:
- Whispering gallery resonators (WGRs) offer unique optical properties but face challenges in simultaneous resonance and phase-matching for nonlinear processes like second-harmonic generation (SHG).
- Discrete frequency spectra of WGRs often prevent simultaneous fulfillment of resonance and phase-matching conditions for interacting waves.
Purpose of the Study:
- To develop a theoretical model for second-harmonic generation (SHG) in whispering gallery resonators (WGRs) that accounts for non-zero frequency detunings.
- To investigate the impact of frequency detunings on resonance line shapes and SHG efficiency in WGRs.
- To experimentally validate the developed model using a lithium niobate WGR.
Main Methods:
- Development of a theoretical model for SHG in WGRs incorporating pump and second-harmonic frequency detunings.
- Analysis of resonance line shape distortions based on relative linewidths.
- Experimental implementation using a lithium niobate WGR to measure SHG efficiency as a function of detuning.
- Comparison of experimental results with model predictions for both lithium niobate and cadmium silicon phosphide WGRs.
Main Results:
- The model predicts significant distortions in pump and second-harmonic resonance line shapes when linewidths are similar, which are absent when the second-harmonic linewidth is much larger.
- The SHG efficiency is accurately described as a function of detuning.
- Excellent quantitative agreement was achieved between the model predictions and experimental results for SHG efficiency in a lithium niobate WGR.
- The model correctly predicted the absence of resonance distortions in the lithium niobate WGR and their presence in the cadmium silicon phosphide WGR, correlating with their respective resonance linewidths.
Conclusions:
- The developed model provides an accurate description of second-harmonic generation in whispering gallery resonators with frequency detunings.
- The study highlights the crucial role of resonance linewidths in determining the line shape distortions and overall SHG performance.
- Experimental validation confirms the model's predictive power for optimizing nonlinear optical processes in WGRs.
Related Concept Videos
02:32The de Broglie Wavelength
31.3K
In the macroscopic world, objects that are large enough to be seen by the naked eye follow the rules of classical physics. A billiard ball moving on a table will behave like a particle; it will continue traveling in a straight line unless it collides with another ball, or it is acted on by some other force, such as friction. The ball has a well-defined position and velocity or well-defined momentum, p = mv, which is defined by mass m and velocity v at any given moment. This is the typical...
31.3K
01:14Sound Waves: Resonance
2.9K
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...
2.9K
01:28Standing Waves in a Cavity
1.2K
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:
1.2K
02:16Resonance and Hybrid Structures
22.4K
According to the theory of resonance, if two or more Lewis structures with the same arrangement of atoms can be written for a molecule, ion, or radical, the actual distribution of electrons is an average of that shown by the various Lewis structures.
Resonance Structures and Resonance Hybrids
The Lewis structure of a nitrite anion (NO2−) may actually be drawn in two different ways, distinguished by the locations of the N–O and N=O bonds.
Resonance Structures and Resonance Hybrids
The Lewis structure of a nitrite anion (NO2−) may actually be drawn in two different ways, distinguished by the locations of the N–O and N=O bonds.
22.4K
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
1.2K
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
1.2K