A new description of Earth's wobble modes using Clairaut coordinates 2: results and inferences on the core mode spectrum

A method for controlling the excitation of cladding modes by tapering special fiber insertions made of SM450 and coreless fibers is proposed. The coupling coefficients between the core mode and the cladding modes of the tapered fiber insertion are calculated. For the calculation, changes in the effective refractive indices and phases of the fiber core and in the cladding modes upon tapering are found. The field distribution of the core mode of the standard fiber transmitted through fiber insertion is obtained. The transmission characteristics of insertions of SM450 and coreless fibers during tapering are simulated and compared with the experiment. The possibility of controlling the transmission and excitation of various cladding modes is confirmed experimentally.

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Phase Dislocations in Hollow Core Waveguides

Fibers ◽

10.3390/fib9100059 ◽

2021 ◽

Vol 9 (10) ◽

pp. 59

Author(s):

Andrey Pryamikov

Keyword(s):

Electric Fields ◽

Rotational Symmetry ◽

Vortex Formation ◽

Hollow Core ◽

Core Mode ◽

Field Phase ◽

The Core ◽

Light Localization ◽

Air Core ◽

Basic Concepts

This paper discusses the basic concepts of phase dislocations and vortex formation in the electric fields of fundamental air core mode of hollow core waveguides with specific types of rotational symmetry of the core‐cladding boundary. Analysis of the behavior of the electric field phase in the transmission bands shows that the mechanism of light localization in the hollow core waveguides with discrete rotational symmetry of the core-cladding boundary cannot be completely described by the ARROW model. For an accurate description of the phase behavior, it is necessary to account for phase jumps of the magnitude of π when passing through the phase dislocations.

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A Novel In-Line Fiber Mach–Zehnder Interferometer Temperature Sensor Made of Thermally Expanded Core Fiber

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.635-637.856 ◽

2014 ◽

Vol 635-637 ◽

pp. 856-859 ◽

Cited By ~ 1

Author(s):

Ying Wu Zhou ◽

Sheng Yu Chen

Keyword(s):

Temperature Sensor ◽

Low Cost ◽

Single Mode ◽

Single Mode Fiber ◽

Zehnder Interferometer ◽

Core Mode ◽

Temperature Changes ◽

The Core ◽

Core Fiber ◽

Mach Zehnder Interferometer

A novel in-line fiber temperature sensor by splicing a piece of single mode fiber between two thermally expanded core fibers at their core-expanded ends is proposed and demonstrated. This structure forms an all fiber Mach–Zehnder interferometer due to the interference between the core mode and the cladding modes of the single mode fiber. The fabricated sensor is applied to measure temperature changes. The temperature sensitivity of the sensor at a length of 6.3cm is about 65.3 pm/°C. The proposed sensor is low cost, easily fabricated, and may be useful for detection of temperature.

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Improving the Sensitivity of Humidity Sensor Based on Mach-Zehnder Interferometer Coated with a Methylcellulose

International Journal of Optics ◽

10.1155/2018/5680128 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5 ◽

Cited By ~ 4

Author(s):

Jun Huang ◽

Bowen Wang ◽

Kai Ni

Keyword(s):

Refractive Index ◽

Humidity Sensor ◽

Single Mode ◽

Single Mode Fiber ◽

Zehnder Interferometer ◽

Core Mode ◽

The Core ◽

Intensity Changes ◽

Practical Measurement ◽

Mach Zehnder Interferometer

A novel humidity sensor based on Mach-Zehnder interferometer (MZI) with the single-mode fiber (SMF) coated with methylcellulose (MC) is proposed and experimentally demonstrated. The MZI consists of two waist enlarged structures. Such an all-fiber MZI incorporates an intermodal interference between the core mode and cladding modes. The MC is coated on the surface of the SMF. External humidity changes the refractive index of MC, causing the intensity changes of the interference pattern. The proposed sensor is linearly responsive to refractive humidity (RH) within the range from 45% to 85% RH, with sensitivity of 0.094 dB/%RH. Moreover the insensitivity of the fiber to the temperature makes this structure more suitable for practical measurement.

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Orientation-dependent Fiber-optic Inclinometer Based on Core-offset Michelson Interferometer

10.21203/rs.3.rs-1048984/v1 ◽

2021 ◽

Author(s):

Hua-jie WANG ◽

Lai-fang ZHENG ◽

Jun-sheng ZHANG

Keyword(s):

Fiber Optic ◽

Incident Light ◽

Michelson Interferometer ◽

Orientation Dependence ◽

Asymmetric Structure ◽

Wavelength Modulation ◽

Core Mode ◽

The Core ◽

Cladding Mode ◽

Mode A

Abstract An in-fiber Michelson interferometer (MI) inclinometer, which consists of misalignment-spliced fiber with end coating, is proposed and experimentally demonstrated. The incident light divided at the misalignment-spliced joint is reflected at the end coating, and then re-coupled into the core of the fiber. Due to the phase difference between the core mode and the cladding mode, a typical Michelson interference is obtained. The fiber near the misalignment-spliced joint is inserted in two capillary quartz tubes. The inclination of the capillary quartz tube leads to a significant deformation and curvature of the misalignment-spliced joint, which causes the wavelength and amplitude of the MI spectrum to change. The experimental results indicate a good response within the angle range of 0º to 50º. Both the wavelength modulation and intensity modulation are realized, with sensitivities of 0.55 nm/deg and 0.17 dB/deg, respectively. Moreover, the sensor shows a strong orientation dependence due to the asymmetric structure in the misalignment-spliced joint.

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High-Sensitivity Refractive Index Sensor Based on a Cascaded Core-Offset and Macrobending Single-Mode Fiber Interferometer

Frontiers in Materials ◽

10.3389/fmats.2020.595437 ◽

2021 ◽

Vol 7 ◽

Author(s):

Chuanxin Teng ◽

Yongjie Zhu ◽

Fangda Yu ◽

Shijie Deng ◽

Libo Yuan ◽

...

Keyword(s):

Refractive Index ◽

High Sensitivity ◽

Single Mode ◽

Spectral Shift ◽

Single Mode Fiber ◽

Refractive Index Sensor ◽

Core Mode ◽

Fiber Core ◽

The Core ◽

Modal Interference

A high-sensitivity Mach–Zehnder interferometer (MZI) based on the cascaded core-offset and macrobending fiber structure is proposed for refractive index (RI) measurement. The core-offset structure makes the fiber core mode couple to the cladding modes, and some of them recouple back to the fiber core at the macrobending structure forming a model interference effect. The liquid RI can be measured by monitoring the spectral shift of the modal interference. The RI sensing performances for the interferometers with different macrobending radii and core offsets are investigated experimentally. Experimental results show that when the core offset is 2 μm and the macrobending radius is 5.5 mm, the sensitivity can reach 699.95 nm/RIU for the RI of 1.43. The temperature dependence for the proposed sensor is also tested, and a temperature sensitivity of 0.112 nm/°C is obtained.

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Noise limitations in the core-mode band of superconducting gravimeter data

Physics of The Earth and Planetary Interiors ◽

10.1016/0031-9201(95)05082-m ◽

1995 ◽

Vol 90 (3-4) ◽

pp. 169-181 ◽

Cited By ~ 35

Author(s):

Olivia Jensen ◽

Jacques Hinderer ◽

David J. Crossley

Keyword(s):

Superconducting Gravimeter ◽

Core Mode ◽

The Core

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What face familiarity feelings say about the lateralization of specific entities within the core system

Behavioral and Brain Sciences ◽

10.1017/s0140525x19001778 ◽

2019 ◽

Vol 42 ◽

Author(s):

Guido Gainotti

Keyword(s):

Temporal Lobe ◽

Memory System ◽

Core System ◽

The Core ◽

Memory Traces ◽

Specific Memory ◽

Target Article ◽

Temporal Structures ◽

The Right

Abstract The target article carefully describes the memory system, centered on the temporal lobe that builds specific memory traces. It does not, however, mention the laterality effects that exist within this system. This commentary briefly surveys evidence showing that clear asymmetries exist within the temporal lobe structures subserving the core system and that the right temporal structures mainly underpin face familiarity feelings.

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A scanning electron microscopic study on dissolving process of cholesterol gallstones by chenodeoxycholic acid (CDCA)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083485 ◽

1978 ◽

Vol 36 (2) ◽

pp. 522-523

Author(s):

T. Kanetaka ◽

M. Cho ◽

S. Kawamura ◽

T. Sado ◽

K. Hara

Keyword(s):

Electron Microscope ◽

Chenodeoxycholic Acid ◽

Outer Surface ◽

Electron Microscopic ◽

Cholesterol Gallstones ◽

The Core ◽

Scanning Electron Microscopic Study ◽

Scanning Electron Microscopic ◽

Acceleration Voltage ◽

Scanning Electron

The authors have investigated the dissolution process of human cholesterol gallstones using a scanning electron microscope(SEM). This study was carried out by comparing control gallstones incubated in beagle bile with gallstones obtained from patients who were treated with chenodeoxycholic acid(CDCA).The cholesterol gallstones for this study were obtained from 14 patients. Three control patients were treated without CDCA and eleven patients were treated with CDCA 300-600 mg/day for periods ranging from four to twenty five months. It was confirmed through chemical analysis that these gallstones contained more than 80% cholesterol in both the outer surface and the core.The specimen were obtained from the outer surface and the core of the gallstones. Each specimen was attached to alminum sheet and coated with carbon to 100Å thickness. The SEM observation was made by Hitachi S-550 with 20 kV acceleration voltage and with 60-20, 000X magnification.

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The Structure and Development of Microbodies in the Fat Body and other Tissues of an Insect (Calpodes Ethlius)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006773x ◽

1970 ◽

Vol 28 ◽

pp. 148-149

Author(s):

M. Locke ◽

J. T. McMahon

Keyword(s):

Electron Microscopy ◽

Liquid Crystals ◽

Fat Body ◽

Competitive Inhibitor ◽

Dense Core ◽

Urate Oxidase ◽

Blood Proteins ◽

Free Base ◽

The Core ◽

The Matrix

The fat body of insects has always been compared functionally to the liver of vertebrates. Both synthesize and store glycogen and lipid and are concerned with the formation of blood proteins. The comparison becomes even more apt with the discovery of microbodies and the localization of urate oxidase and catalase in insect fat body.The microbodies are oval to spherical bodies about 1μ across with a depression and dense core on one side. The core is made of coiled tubules together with dense material close to the depressed membrane. The tubules may appear loose or densely packed but always intertwined like liquid crystals, never straight as in solid crystals (Fig. 1). When fat body is reacted with diaminobenzidine free base and H2O2 at pH 9.0 to determine the distribution of catalase, electron microscopy shows the enzyme in the matrix of the microbodies (Fig. 2). The reaction is abolished by 3-amino-1, 2, 4-triazole, a competitive inhibitor of catalase. The fat body is the only tissue which consistantly reacts positively for urate oxidase. The reaction product is sharply localized in granules of about the same size and distribution as the microbodies. The reaction is inhibited by 2, 6, 8-trichloropurine, a competitive inhibitor of urate oxidase.

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