Optical microfibers and nanofibers

AbstractAs a combination of fiber optics and nanotechnology, optical microfibers and nanofibers (MNFs) have been emerging as a novel platform for exploring fiber-optic technology on the micro/nanoscale. Typically, MNFs taper drawn from glass optical fibers or bulk glasses show excellent surface smoothness, high homogeneity in diameter and integrity, which bestows these tiny optical fibers with low waveguiding losses and outstanding mechanical properties. Benefitting from their wavelength- or sub-wavelength-scale transverse dimensions, waveguiding MNFs exhibit a number of interesting properties, including tight optical confinement, strong evanescent fields, evident surface field enhancement and large and abnormal waveguide dispersion, which makes them ideal nanowaveguides for coherently manipulating light, and connecting fiber optics with near-field optics, nonlinear optics, plasmonics, quantum optics and optomechanics on the wavelength- or sub-wavelength scale. Based on optical MNFs, a variety of technological applications, ranging from passive micro-couplers and resonators, to active devices such as lasers and optical sensors, have been reported in recent years. This review is intended to provide an up-to-date introduction to the fabrication, characterization and applications of optical MNFs, with emphasis on recent progress in our research group. Starting from a brief introduction of fabrication techniques for physical drawing glass MNFs in Section 2, we summarize MNF optics including waveguiding modes, evanescent coupling, and bending loss of MNFs in Section 3. In Section 4, starting from a “MNF tree” that summarizes the applications of MNFs into 5 categories (waveguide & near field optics, nonlinear optics, plasmonics, quantum & atom optics, optomechanics), we go to details of typical technological applications of MNFs, including optical couplers, interferometers, gratings, resonators, lasers and sensors. Finally in Section 5 we present a brief summary of optical MNFs regarding their current challenges and future opportunities.

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Ultra-high-Q resonances in plasmonic metasurfaces

Nature Communications ◽

10.1038/s41467-021-21196-2 ◽

2021 ◽

Vol 12 (1) ◽

Cited By ~ 2

Author(s):

M. Saad Bin-Alam ◽

Orad Reshef ◽

Yaryna Mamchur ◽

M. Zahirul Alam ◽

Graham Carlow ◽

...

Keyword(s):

Incident Light ◽

Reducing Power ◽

Field Enhancement ◽

Plasmonic Nanostructures ◽

High Q ◽

Alternative Material ◽

Order Of Magnitude ◽

Wavelength Scale ◽

Strong Confinement ◽

Sub Wavelength

AbstractPlasmonic nanostructures hold promise for the realization of ultra-thin sub-wavelength devices, reducing power operating thresholds and enabling nonlinear optical functionality in metasurfaces. However, this promise is substantially undercut by absorption introduced by resistive losses, causing the metasurface community to turn away from plasmonics in favour of alternative material platforms (e.g., dielectrics) that provide weaker field enhancement, but more tolerable losses. Here, we report a plasmonic metasurface with a quality-factor (Q-factor) of 2340 in the telecommunication C band by exploiting surface lattice resonances (SLRs), exceeding the record by an order of magnitude. Additionally, we show that SLRs retain many of the same benefits as localized plasmonic resonances, such as field enhancement and strong confinement of light along the metal surface. Our results demonstrate that SLRs provide an exciting and unexplored method to tailor incident light fields, and could pave the way to flexible wavelength-scale devices for any optical resonating application.

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Laser Micro-Machining Using Near-Field Nano-Optics

Manufacturing Engineering and Materials Handling Engineering ◽

10.1115/imece2004-60615 ◽

2004 ◽

Cited By ~ 1

Author(s):

Haseung Chung ◽

Katsuo Kurabayashi ◽

Suman Das

Keyword(s):

Data Storage ◽

Near Field ◽

Numerical Aperture ◽

Near Field Optics ◽

Incident Laser Power ◽

Scanning Optical Microscopy ◽

Near Field Effect ◽

Near Field Scanning ◽

Feature Resolution ◽

Sub Wavelength

Solid immersion lenses (SIL) facilitate high numerical aperture (NA) and consequent sub-wavelength diffraction limited focusing in near-field optics based systems. Such systems are in commercial and research use for various applications including near-field scanning optical microscopy, ultra-high density magneto-optic data storage and near-field nanolithography. Here, we present a novel nanomanufacturing method using SIL-based near-field optics for laser-induced sub-micron patterning on silicon wafers. The near-field effect of SILs was investigated by using hemispherical BK7 lenses (n=1.5196, NA=0.9237) to superfocus an incident Q-switched, 532nm Nd:YAG laser beam transmitted through a focusing objective. This optical arrangement achieved a laser-processed feature resolution near the diffraction limit in air. Results of experiments that were conducted at various processing conditions to investigate the effects of varying incident laser power (with average pulse power less than 1W), pulse repetition rate, pulse width, number of pulses and size of SIL on processed feature size and resolution are presented.

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Surface-Plasmons-Assisted Nanoscale Photolithography

Design, Synthesis, and Applications ◽

10.1115/nano2005-87058 ◽

2005 ◽

Author(s):

Dongbing Shao ◽

Shaochen Chen

Keyword(s):

Low Cost ◽

Near Field ◽

Optical Diffraction ◽

Scanning Probe ◽

Fabrication Technology ◽

Scanning Probe Lithography ◽

Low Contrast ◽

The Past ◽

Wavelength Scale ◽

Sub Wavelength

Photolithography has remained a useful micro-fabrication technology because of its high throughput, low cost, simplicity, and reproducibility over the past several decades. However its resolution is limited at a sub-wavelength scale due to optical diffraction. Among all different approaches to overcoming this problem, such as electron-beam lithography, imprint lithography and scanning probe lithography, near-field optical lithography inherits many merits of the traditional photolithography method. Major drawbacks of this approach include low contrast, low transmission and low density.

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Near-field plasmon-resonance scanning microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136611 ◽

1995 ◽

Vol 53 ◽

pp. 48-49

Author(s):

Sheldon Schultz

Keyword(s):

Plasmon Resonance ◽

Near Field ◽

Far Field ◽

Lateral Size ◽

Physical Sciences ◽

Signal To Noise ◽

Near Field Optics ◽

The Past ◽

Plane Light ◽

Sub Wavelength

In the past few years the field of near-field scanning optical microscopy (NSOM) has developed rapidly with applications spanning all the physical sciences. A key goal of this form of microscopy is to obtain resolution at levels well beyond those possible with the usual far-field optics. In contrast to far-field optics, which is bounded by the well known limits imposed by diffraction, near-field optics has no "in principle" fundamental lower limit in lateral size, at least down to atomic dimensions, although in practice, signal-to-noise considerations may restrict the application of NSOM to a few nanometers.The simplest form of NSOM to visualize is based on the principle of a sub-wavelength aperture (with D/λ < < 1) in an opaque plane. Light impinging on this aperture may only be transmitted through the diameter D, and, indeed, were it observed in the far-field, would be spread out over the entire half space due to diffraction. However, if the sample to be studied is placed in the near-field of the aperture, say within a distance D away, the region illuminated will also be restricted to a lateral dimension very close to D.

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Nonlinear Optics in Waveguide Arrays and Photonic Nanowires

Communications in Physics ◽

10.15625/0868-3166/27/1/9001 ◽

2017 ◽

Vol 27 (1) ◽

pp. 1

Author(s):

Tran Xuan Truong

Keyword(s):

Nonlinear Optics ◽

Optical Fibers ◽

Light Propagation ◽

Nonlinear Phenomena ◽

Recoil Effect ◽

Waveguide Arrays ◽

Vector Mode ◽

New Equation ◽

Discrete Solitons ◽

Sub Wavelength

In this paper we review our works in the field of nonlinear optics in waveguide arrays (WAs) and photonic nanowires. We first focus on the new equation governing light propagation in optical fibers with sub-wavelength cores which simultaneously takes into account (i) the vector nature of the electromagnetic modes inside fibers, (ii) the strong dispersion of the nonlinearity inside the spectral body of the pulse, (iii) and the full variations of the vector mode profiles with frequency. From this equation we have shown that a new kind of nonlinearity emerges in subwavelength-core fibers which can suppress the Raman self-frequency shift of solitons. We then discuss some nonlinear phenomena in WAs such as the emission of the diffractive resonant radiation from spatial discrete solitons and the anomalous recoil effect. Finally, we review our works on the optical analogues of Dirac solitons in quantum relativistic physics in binary waveguide arrays (BWAs) for both fundamental and higher-order solitons, and its interaction.

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Comprehensive Review Tapered Optical Fiber Configurations for Sensing Application: Trend and Challenges

Biosensors ◽

10.3390/bios11080253 ◽

2021 ◽

Vol 11 (8) ◽

pp. 253

Author(s):

Bakr Ahmed Taha ◽

Norazida Ali ◽

Nurfarhana Mohamad Sapiee ◽

Mahmoud Muhanad Fadhel ◽

Ros Maria Mat Yeh ◽

...

Keyword(s):

Optical Tweezers ◽

Optical Fibers ◽

Optical Sensors ◽

Fiber Grating ◽

Absorption Properties ◽

Wavelength Scale ◽

Tapered Optical Fiber ◽

Period Fiber Grating ◽

Loop Ring ◽

Analysis Of Performance

Understanding environmental information is necessary for functions correlated with human activities to improve healthcare quality and reduce ecological risk. Tapered optical fibers reduce some limitations of such devices and can be considerably more responsive to fluorescence and absorption properties changes. Data have been collected from reliable sources such as Science Direct, IEEE Xplore, Scopus, Web of Science, PubMed, and Google Scholar. In this narrative review, we have summarized and analyzed eight classes of tapered-fiber forms: fiber Bragg grating (FBG), long-period fiber grating (LPFG), Mach–Zehnder interferometer (MZI), photonic crystals fiber (PCF), surface plasmonic resonance (SPR), multi-taper devices, fiber loop ring-down technology, and optical tweezers. We evaluated many issues to make an informed judgement about the viability of employing the best of these methods in optical sensors. The analysis of performance for tapered optical fibers depends on four mean parameters: taper length, sensitivity, wavelength scale, and waist diameter. Finally, we assess the most potent strategy that has the potential for medical and environmental applications.

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Fiber Optics for Propulsion Control Systems

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.3239822 ◽

1985 ◽

Vol 107 (4) ◽

pp. 851-855

Author(s):

R. J. Baumbick

Keyword(s):

Full Advantage ◽

Control Systems ◽

Fiber Optics ◽

Optical Fibers ◽

Optical Sensors ◽

Optical Waveguides ◽

Dielectric Waveguides ◽

Sensors And Actuators ◽

Propulsion Systems ◽

Propulsion Control

The term “fiber optics” means the use of dielectric waveguides to transfer information. In aircraft systems with digital controls, fiber optics has advantages over wire systems because of its inherent immunity to electromagnetic noise (EMI) and electromagnetic pulses (EMP). It also offers a weight benefit when metallic conductors are replaced by optical fibers. To take full advantage of the benefits of optical waveguides, passive optical sensors are also being developed to eliminate the need for electrical power to the sensor. Fiber optics may also be used for controlling actuators on engine and airframe. In this application, the optical fibers, connectors, etc., will be subjected to high temperatures and vibrations. This paper discusses the use of fiber optics in aircraft propulsion systems, together with the optical sensors and optically controlled actuators being developed to take full advantage of the benefits which fiber optics offers. The requirements for sensors and actuators in advanced propulsion systems are identified. The benefits of using fiber optics in place of conventional wire systems are discussed as well as the environmental conditions under which the optical components must operate. Work being done under contract to NASA Lewis on optical and optically activated actuators sensors for propulsion control systems is presented.

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Near-field optics: Direct observation of the field enhancement below an apertureless probe using a photosensitive polymer

Applied Physics Letters ◽

10.1063/1.1425083 ◽

2001 ◽

Vol 79 (24) ◽

pp. 4019-4021 ◽

Cited By ~ 50

Author(s):

Fekhra H’dhili ◽

Renaud Bachelot ◽

Gilles Lerondel ◽

Dominique Barchiesi ◽

Pascal Royer

Keyword(s):

Direct Observation ◽

Near Field ◽

Field Enhancement ◽

Near Field Optics ◽

Photosensitive Polymer

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Near-field optics for nanoprocessing

Advanced Optical Technologies ◽

10.1515/aot-2015-0054 ◽

2016 ◽

Vol 5 (1) ◽

Cited By ~ 5

Author(s):

Mitsuhiro Terakawa ◽

Nikolay N. Nedyalkov

Keyword(s):

Laser Processing ◽

Recent Progress ◽

Coupling Effect ◽

Near Field ◽

Field Enhancement ◽

Mie Scattering ◽

Diffraction Limit ◽

Near Field Optics ◽

Potential Applications ◽

Plasmon Polariton

AbstractThe recent progress in laser processing reaches a level where a precise fabrication that overcomes the diffraction limit of the far-field optics can be achieved. Laser processing mediated by enhanced near field is one of the attractive methods to provide highly precise structuring with a simple apparatus. In this review, we describe the fundamentals of the electromagnetic near field in the vicinity of small structures and the application of its specific properties for nanomodification. Theoretical and experimental results on nanoablation based on electromagnetic field enhancement due to plasmon polariton excitation and Mie scattering are discussed. High-throughput nanohole fabrication mediated by arrayed nanospheres is discussed, as the coupling effect of near field is also considered. In addition, recent fabrication techniques and their potential applications in nanopatterning, nanoscale deformation, and biophotonics are discussed.

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