Subwavelength Silicon Microdisks with High Quality Factors

We report the fabrication of crystalline microresonators of high quality (Q) factors with a controllable wedge angle on lithium niobate on insulator (LNOI). Our technique relies on a femtosecond laser assisted chemo-mechanical polish, which allows us to achieve ultrahigh surface smoothness as critically demanded by high Q microresonator applications. We show that by refining the polish parameters, Q factors as high as 4.7 × 107 can be obtained and the wedge angle of the LNOI can be continuously tuned from 9° to 51°.

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Unidirectional reflectionlessness and nonreciprocal perfect absorption in optical waveguide system based on phase coupling between two photonic crystal cavities

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863518500042 ◽

2018 ◽

Vol 27 (01) ◽

pp. 1850004 ◽

Cited By ~ 2

Author(s):

Shu Jing Liu ◽

Cong Zhang ◽

Ruiping Bai ◽

Xintong Gu ◽

Hong Da Yin ◽

...

Keyword(s):

Photonic Crystal ◽

Optical Waveguide ◽

Quality Factors ◽

Phase Coupling ◽

High Quality ◽

Perfect Absorption ◽

Photonic Crystal Cavities ◽

Exceptional Points ◽

Waveguide System ◽

Distance Formula

We demonstrate the unidirectional reflectionlessness at exceptional points (EPs) and nonreciprocal perfect absorption near EPs based on phase coupling between two photonic crystal cavities (PCCs) in optical waveguide. In our scheme, when distance [Formula: see text][Formula: see text]nm ([Formula: see text][Formula: see text]nm), the reflectivities for forward and backward (backward and forward) directions are closed to [Formula: see text] and [Formula: see text] ([Formula: see text] and [Formula: see text]), respectively, and absorptances of the nonreciprocal perfect absorptions for forward and backward directions are [Formula: see text] and [Formula: see text] with the high quality factors of [Formula: see text] and [Formula: see text], respectively.

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Electrofluidic Assembly of Nanoelectromechanical Systems

MRS Proceedings ◽

10.1557/proc-687-b4.4 ◽

2001 ◽

Vol 687 ◽

Cited By ~ 1

Author(s):

Stephane Evoy ◽

Ben Hailer ◽

Martin Duemling ◽

Benjamin R. Martin ◽

Thomas E. Mallouk ◽

...

Keyword(s):

Nanoelectromechanical Systems ◽

Quality Factors ◽

Top Down ◽

High Quality ◽

Resonant Frequencies ◽

Surface Machining ◽

Sensor Applications ◽

Surface Assembly ◽

Manufacturing Technologies ◽

20 Nm

AbstractRecent advances in surface nanomachining have allowed the fabrication of mechanical structures with dimensions reaching 20 nm, and resonant frequencies in the 100s of MHz. Structural issues prevent the “top-down” surface machining of high-quality NEMS resonators. Such systems are alternatively to be bestowed by “bottom-up” manufacturing technologies. We report the surface assembly of RF-range NEMS. Using electrofluidic assembly, we have successfully positioned Rh mechanical beams onto specific sites of a silicon circuit. With diameters as small as 250 nm and lengths varying from 2 to 3 [.proportional]m, preliminary results show mechanical resonances ranging from 5 MHz to 80 MHz, and quality factors reaching 500. We also report the development of nanostructured NEMS for sensor applications, and present strategies for their deployment in integrative nanosystems.

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Measuring and Reporting High Quality Factors of Inductors Using Vector Network Analyzers

IEEE Transactions on Microwave Theory and Techniques ◽

10.1109/tmtt.2010.2042843 ◽

2010 ◽

Vol 58 (4) ◽

pp. 1046-1055 ◽

Cited By ~ 22

Author(s):

William B Kuhn ◽

Adam P Boutz

Keyword(s):

Quality Factors ◽

High Quality ◽

Vector Network Analyzers ◽

Network Analyzers

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Versatile architecture of ultra-narrow band absorbing photonic nanostructure

EPJ Web of Conferences ◽

10.1051/epjconf/202023805005 ◽

2020 ◽

Vol 238 ◽

pp. 05005

Author(s):

Clément Verlhac ◽

Hasnaa El-Ouazzani ◽

Mathilde Makhsiyan ◽

Riad Haidar ◽

Jérôme Primot ◽

...

Keyword(s):

Absorption Spectra ◽

Loss Rate ◽

Narrow Band ◽

Quality Factors ◽

High Quality ◽

Precise Control ◽

Guided Mode ◽

Very High ◽

Metallic Waveguide ◽

Mode Resonator

Ultra narrow-band absorbing surfaces answer a growing demand of precise control of absorption spectra. Starting from a design of guided mode resonator (GMR), we present here a versatile architecture presenting resonances of very high quality factors (up to 10 000) and spectrally adjustable. This design uses multiple slices of dielectrics to focus resonating field in the middle of a metallic waveguide, diminishing its extension in the metal and thus the loss rate of the propagating mode.

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How do sheep and beef farmers manage pasture quality?

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.2000.62.2378 ◽

2000 ◽

pp. 117-121

Author(s):

M.G. Lambert ◽

M.S. Paine ◽

G.W. Sheath ◽

R.W. Webby ◽

A.J. Litherlandr ◽

...

Keyword(s):

Management Practices ◽

Parasite Control ◽

Quality Factors ◽

High Quality ◽

Factors Affecting ◽

Internal Parasite ◽

Pasture Quality ◽

Morphological Composition ◽

Fertiliser Application ◽

Irrigation Drainage

Four groups of sheep and beef farmers located throughout New Zealand were asked questions relating to pasture quality management. Answers were grouped into themes. In answer to the question "what do you do to manage pasture quality", themes identified were manipulation of wholefarm feed demand throughout the year to match feed supply; use of specific grazing strategies; topping and mowing; cropping and regrassing; fertiliser application; weed and pest control; conservation and supplementation; monitoring, predicting and planning; irrigation, drainage and aeration; and internal parasite control. In answer to the question "what is pasture quality", themes identified were animal performance; chemical composition of the herbage; botanical and morphological composition of the herbage; factors affecting intake and utilisation; and anti-quality factors. Most management practices were designed to control the spring surplus or provide alternative high quality feed through cropping or regrassing. Keywords: current practices, farmers, management, pasture quality, sheep and beef

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A Multiple-Beam Tuning-Fork Gyroscope With High Quality Factors

Volume 12: Micro and Nano Systems, Parts A and B ◽

10.1115/imece2009-10454 ◽

2009 ◽

Author(s):

Ren Wang ◽

Shiva Krishna Durgam ◽

Zhili Hao ◽

Linda Vahala

Keyword(s):

Tuning Fork ◽

Rate Sensitivity ◽

Sense Mode ◽

Quality Factors ◽

Drive Mode ◽

High Quality ◽

Multiple Beam ◽

Frequency Split ◽

Operation Frequency ◽

Mask Fabrication

This paper reports on the design, fabrication, and testing of a multiple-beam tuning-fork gyroscope featuring high Quality factors (Q). A multiple-beam tuning-fork structure is designed to achieve high Qs in its drive mode and sense mode. The gyroscope is fabricated on a 30μm-thick SOI wafer using a one-mask fabrication process. The measured Qs of the fabricated gyroscope are 162,060 in the drive-mode and 85,168 in the sense mode at an operation frequency of 16.8kHz. Under a frequency split of 6Hz, the prototype device demonstrates a rate sensitivity of 0.02mV/°/sec.

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