A Neck-down Microsphere Resonator with an Improved Quality Factor of the Whispering-Gallery Mode

Dye-doped polystyrene (DDPS) encapsulated in a silica-glass capillary with a diameter of 300 μm was fabricated through radical polymerization of styrene within the capillary. The coherent random lasing (RL) with full width at half maximum (FWHM) of 0.36 nm and a quality factor of 1608 was produced in the DDPS with the capillary when pumping at 532 nm. However, the incoherent RL with FWHM of 6.62 nm and a quality factor of 92 was produced in the DDPS without the capillary. A detailed investigation on this phenomenon by changing the diameter of the capillary and core refractive index (RI) reveals that there exists a strong whispering gallery mode (WGM) resonance in the capillary, which helps generate the coherent RL. The findings may open up a new approach for the fabrication of highly efficient photonic devices.

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Quantitative phase imaging for surface roughness measurements to demonstrate variation of quality factor in crystalline whispering-gallery mode resonators (Conference Presentation)

Photonic Instrumentation Engineering VI ◽

10.1117/12.2509408 ◽

2019 ◽

Author(s):

Maxime Jacquot ◽

Guoping Lin ◽

Aurélien Coillet ◽

Souleymane Diallo ◽

Laurent Larger ◽

...

Keyword(s):

Surface Roughness ◽

Quality Factor ◽

Whispering Gallery Mode ◽

Phase Imaging ◽

Quantitative Phase Imaging ◽

Quantitative Phase ◽

Whispering Gallery ◽

Roughness Measurements

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Boundary rounding effect in the hexagonal and oval two-dimensional optical microcavity

Modern Physics Letters B ◽

10.1142/s0217984921501463 ◽

2021 ◽

pp. 2150146

Author(s):

Canran Zhang ◽

Jun Dai

Keyword(s):

Quality Factor ◽

Whispering Gallery Mode ◽

Circular Cavity ◽

Structure Parameter ◽

The Finite Element Method ◽

Optical Mode ◽

Optical Microcavity ◽

Whispering Gallery ◽

Mode Pattern ◽

Simulation Results

In this paper, the boundary rounding effects of two types of non-circular GaN microcavity system are numerically simulated by the finite element method. When the rounding parameter [Formula: see text] of the hexagonal microcavity decreases, the six corners of the regular hexagon are gradually rounded, the results show that the optical mode gradually changes from the hexagonal whispering-gallery mode (WGM) to the perfect circular WGM, and the quality factor of the modes increases correspondingly. For the oval microcavity, the structure parameter [Formula: see text] increases from 0 to 1 when the oval microcavity gradually changes from a stadium cavity to a circular cavity. The simulation results show that the quality factor increases with [Formula: see text], and the optical mode changes from high-leak mode to WGM. Our results demonstrate the effect of the boundary rounding on the mode pattern and quality factor in hexagonal and oval microcavities.

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Finite element realization of ultra-high quality factor frequency-temperature compensated sapphire-rutile whispering gallery mode resonators

1999 IEEE MTT-S International Microwave Symposium Digest (Cat. No.99CH36282) ◽

10.1109/mwsym.1999.779631 ◽

2003 ◽

Cited By ~ 7

Author(s):

M.E. Tobar ◽

D. Cros ◽

P. Blondy ◽

J.G. Hartnett ◽

P. Guillon

Keyword(s):

Finite Element ◽

Quality Factor ◽

Whispering Gallery Mode ◽

High Quality Factor ◽

High Quality ◽

Whispering Gallery ◽

Factor Frequency ◽

Frequency Temperature

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Radiation Transfer in Whispering-Gallery Mode Microcavities

Heat Transfer, Part B ◽

10.1115/imece2005-80012 ◽

2005 ◽

Author(s):

Haiyong Quan ◽

Zhixiong Guo

Keyword(s):

Quality Factor ◽

Energy Transport ◽

Radiation Transfer ◽

Free Spectral Range ◽

Radiation Energy ◽

Whispering Gallery Mode ◽

Whispering Gallery ◽

Waveguide Width ◽

Scattering Spectra ◽

Spectral Ranges

Micro/nanoscale radiation transfer in whispering-gallery mode (WGM) microcavities is investigated. Each cavity consists of a waveguide and a microdisk coupled in a planar chip. In order to characterize the WGM resonance phenomena, studies of configuration parameters, specifically the microdisk size, the gap distance separating the microdisk and waveguide, and the waveguide width are numerically conducted. The finite element method is used for solving Maxwell’s equations which govern the propagation of electromagnetic (EM) field and the radiation energy transport in the micro/nanoscale WGM structures. The EM fields and the radiation energy distributions in the microcavities are then obtained. The scattering spectra for three different microdisk sizes are also obtained; and through which the WGM resonant properties such as the quality factor, the full-width at half maximum (FWHM), the free spectral range, and the finesse of the resonant modes are analyzed. It is found that the resonant frequencies and their free spectral ranges are predominantly determined by the size of the microcavity; while the FWHM, finesse, and quality factor are strong functions of the gap.

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