Evolution of Whispering Gallery Modes in Li-Doped ZnO Hexagonal Micro- and Nanostructures

The formation of optical cavities in Li-doped ZnO nanostructures was investigated. By means of the vapor–solid method, long micro- and nanostructures with a hexagonal cross-section were grown. These morphologies were favorable for Fabry-Pérot and whispering gallery modes to appear. A variety of structures with different sections was studied using µ-photoluminescence in both the transverse electric (TE) and transverse magnetic (TM) polarizations, showing well-pronounced optical resonant modes. The results showed a dominance of whispering gallery modes that were in good agreement with the calculated refractive index. The quality factor (Q) and finesse (F) were estimated, which demonstrated the quality of Li:ZnO structures as optical cavities.

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Light guiding and optical resonances in ZnS microstructures doped with Ga or In

Journal of Materials Chemistry C ◽

10.1039/c5tc02383a ◽

2015 ◽

Vol 3 (42) ◽

pp. 10981-10989 ◽

Cited By ~ 9

Author(s):

B. Sotillo ◽

P. Fernández ◽

J. Piqueras

Keyword(s):

Whispering Gallery Modes ◽

Optical Cavities ◽

Optical Resonances ◽

Whispering Gallery ◽

Fabry Perot

In this work, the resonant (Fabry–Pérot and whispering gallery) modes in optical cavities based on ZnS microstructures have been studied.

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Fabry–Pérot and whispering gallery modes enhanced luminescence from an individual hexagonal ZnO nanocolumn

Applied Physics Letters ◽

10.1063/1.3474611 ◽

2010 ◽

Vol 97 (4) ◽

pp. 041917 ◽

Cited By ~ 13

Author(s):

N. W. Wang ◽

Y. H. Yang ◽

G. W. Yang

Keyword(s):

Whispering Gallery Modes ◽

Whispering Gallery ◽

Fabry Perot ◽

Enhanced Luminescence

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Detection of Protein Orientation on the Silica Microsphere Surface Using Transverse Electric/Transverse Magnetic Whispering Gallery Modes

Biophysical Journal ◽

10.1529/biophysj.106.103200 ◽

2007 ◽

Vol 92 (12) ◽

pp. 4466-4472 ◽

Cited By ~ 49

Author(s):

Mayumi Noto ◽

David Keng ◽

Iwao Teraoka ◽

Stephen Arnold

Keyword(s):

Transverse Electric ◽

Transverse Magnetic ◽

Whispering Gallery Modes ◽

Silica Microsphere ◽

Protein Orientation ◽

Whispering Gallery

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Quintuple-mode wideband bandpass filters with improved out-of-band rejection

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078719001338 ◽

2019 ◽

Vol 12 (4) ◽

pp. 276-281

Author(s):

Musab Hameed ◽

Gaobiao Xiao ◽

Lina Qiu ◽

Tayyab Hameed

Keyword(s):

Rectangular Waveguide ◽

Bandpass Filters ◽

Transverse Magnetic ◽

Center Frequency ◽

Fractional Bandwidth ◽

Resonant Modes ◽

Coaxial Lines ◽

Good Agreement

AbstractThis paper presents design of quintuple-mode wideband bandpass filters, implemented with off-centered perturbed metallic cylinders in a rectangular waveguide cavity. Three perturbation cylinders are placed at the bottom of the rectangular waveguide cavity, along with a pair of perpendicularly fed coaxial lines; excite five quasi-transverse magnetic modes to realize the desired passband. The height of the waveguide cavity and the shape of the perturbation cylinders are exploited to shift the resonant modes far away from the passband and achieve a good out-of-band rejection and sharp skirt selectivity. The filter operates at the center frequency of 2.68 GHz with a wide fractional bandwidth of 43%. The proposed filter is fabricated with aluminum. The measured and simulated results are in good agreement with each other.

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Analytical Solution of Whispering-Gallery Modes

ASME 2007 InterPACK Conference, Volume 1 ◽

10.1115/ipack2007-33124 ◽

2007 ◽

Author(s):

Haiyong Quan ◽

Zhixiong Guo

Keyword(s):

Separation Of Variables ◽

Whispering Gallery Modes ◽

Mems Devices ◽

High Q ◽

Optical Microcavities ◽

Whispering Gallery ◽

Resonant Modes ◽

Resonance Frequencies ◽

Potential Applications ◽

Dynamic Filters

Advances in MEMS/NEMS techniques have enabled high-Q whispering-gallery modes in integrated microcavities. Potential applications of optical microcavities include quantum informatics, novel micro/nano sources, dynamic filters, and micro/nanosensors. It is important to understand the intrinsic resonant modes of a cavity. In this report, we will analyze whispering-gallery modes in resonators of planar structure which is common in MEMS devices. The wave equation is solved by using the method of separation of variables with appropriate boundary conditions. Analytical formulations are established. The resonance frequencies as well as the electric field distributions in exemplary resonators are presented for a variety of whispering-gallery modes.

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Long Period Grating-Based Fiber Coupling to WGM Microresonators

Micromachines ◽

10.3390/mi9070366 ◽

2018 ◽

Vol 9 (7) ◽

pp. 366 ◽

Cited By ~ 8

Author(s):

Francesco Chiavaioli ◽

Dario Laneve ◽

Daniele Farnesi ◽

Mario Falconi ◽

Gualtiero Nunzi Conti ◽

...

Keyword(s):

Whispering Gallery Modes ◽

Long Period Grating ◽

High Q ◽

Optical Microresonators ◽

Whispering Gallery ◽

Long Period ◽

Thick Fiber ◽

Long Period Gratings ◽

Fiber Taper ◽

Good Agreement

A comprehensive model for designing robust all-in-fiber microresonator-based optical sensing setups is illustrated. The investigated all-in-fiber setups allow light to selectively excite high-Q whispering gallery modes (WGMs) into optical microresonators, thanks to a pair of identical long period gratings (LPGs) written in the same optical fiber. Microspheres and microbubbles are used as microresonators and evanescently side-coupled to a thick fiber taper, with a waist diameter of about 18 µm, in between the two LPGs. The model is validated by comparing the simulated results with the experimental data. A good agreement between the simulated and experimental results is obtained. The model is general and by exploiting the refractive index and/or absorption characteristics at suitable wavelengths, the sensing of several substances or pollutants can be predicted.

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