Anisotropic Radiation in Heterostructured “Emitter in a Cavity” Nanowire

Tailorable synthesis of axially heterostructured epitaxial nanowires (NWs) with a proper choice of materials allows for the fabrication of novel photonic devices, such as a nanoemitter in the resonant cavity. An example of the structure is a GaP nanowire with ternary GaPAs insertions in the form of nano-sized discs studied in this work. With the use of the micro-photoluminescence technique and numerical calculations, we experimentally and theoretically study photoluminescence emission in individual heterostructured NWs. Due to the high refractive index and near-zero absorption through the emission band, the photoluminescence signal tends to couple into the nanowire cavity acting as a Fabry–Perot resonator, while weak radiation propagating perpendicular to the nanowire axis is registered in the vicinity of each nano-sized disc. Thus, within the heterostructured nanowire, both amplitude and spectrally anisotropic photoluminescent signals can be achieved. Numerical modeling of the nanowire with insertions emitting in infrared demonstrates a decay in the emission directivity and simultaneous rise of the emitters coupling with an increase in the wavelength. The emergence of modulated and non-modulated radiation is discussed, and possible nanophotonic applications are considered.

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Broadband and Highly Directional Visible Light Scattering by Laser-Splashed Lossless TiO2 Nanoparticles

Molecules ◽

10.3390/molecules26206106 ◽

2021 ◽

Vol 26 (20) ◽

pp. 6106

Author(s):

Yinan Zhang ◽

Shiren Chen ◽

Jing Han

Keyword(s):

Refractive Index ◽

Tio2 Nanoparticles ◽

Silicon Germanium ◽

High Refractive Index ◽

Photonic Devices ◽

Forward Scattering ◽

Visible Range ◽

Great Promise ◽

Scattering Ratio ◽

On Chip

All-dielectric nanoparticles, as the counterpart of metallic nanostructures have recently attracted significant interest in manipulating light-matter interaction at a nanoscale. Directional scattering, as an important property of nanoparticles, has been investigated in traditional high refractive index materials, such as silicon, germanium and gallium arsenide in a narrow band range. Here in this paper, we demonstrate that a broadband forward scattering across the entire visible range can be achieved by the low loss TiO2 nanoparticles with moderate refractive index. This mainly stems from the optical interferences between the broadband electric dipole and the magnetic dipole modes. The forward/backward scattering ratio reaches maximum value at the wavelengths satisfying the first Kerker’s condition. Experimentally, the femtosecond pulsed laser was employed to splash different-sized nanoparticles from a thin TiO2 film deposited on the glass substrate. Single particle scattering measurement in both the forward and backward direction was performed by a homemade confocal microscopic system, demonstrating the broadband forward scattering feature. Our research holds great promise for many applications such as light harvesting, photodetection and on-chip photonic devices and so on.

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Design of Optical Thin Film Filter for Sensor Network

Journal of Network and Information Security ◽

10.21863/jnis/2015.3.1.002 ◽

2015 ◽

Vol 3 (1) ◽

Author(s):

Vahideh Khadem Hosseini ◽

Mohammad Taghi Ahmadi

Keyword(s):

Thin Film ◽

Refractive Index ◽

Silicon Dioxide ◽

Human Body ◽

High Refractive Index ◽

Structural Factors ◽

Optical Thin Film ◽

Fabry Perot ◽

Detection Of Objects ◽

Low Refractive Index

Human body detection is very important especially in the countries prone to earthquakes. Fabry-Perot filter as an ideal option in this field needs to be explored. This filter is useful for detection of objects that have temperature around that of the human body. In the presented research, an optical thin film Fabry-Perot filter (FPF) at the wavelength about 8 um to 14 um is investigated. The important factors on transmission spectrum and the band width of filter are discussed. Additionally structural factors such as layers material and their thickness are explored. Various materials with high and low refractive index are examined by TFCalc3.5 for thin film layers. Germanium (Ge) with the refractive index 4.20 is selected for layer with high refractive index and Silicon Dioxide (SiO2) with the refractive index 1.46 is selected for low refractive index layer. Our simulation results lead to optimum parameters as: Germanium layer with 196nm thickness and Silicon Dioxide layer with 451nm thickness. Simulation of proposed filter indicated that the transfer coefficient is more than 90% in desired spectrum. Filter structure can be used on Infrared detectors to improve their resolutions and detection.

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High refractive index polymer materials for Photonic devices

PORTABLE-POLYTRONIC 2008 - 2nd IEEE International Interdisciplinary Conference on Portable Information Devices and the 2008 7th IEEE Conference on Polymers and Adhesives in Microelectronics and Photonics ◽

10.1109/portable-polytronic.2008.4681284 ◽

2008 ◽

Author(s):

W. F. Ho ◽

M. A. Uddin ◽

H. P. Chan

Keyword(s):

Refractive Index ◽

High Refractive Index ◽

Photonic Devices ◽

Polymer Materials

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High refractive index in wurtzite GaP measured from Fabry-Pérot resonances

Applied Physics Letters ◽

10.1063/1.4947443 ◽

2016 ◽

Vol 108 (17) ◽

pp. 173101 ◽

Cited By ~ 4

Author(s):

S. Assali ◽

D. van Dam ◽

J. E. M. Haverkort ◽

E. P. A. M. Bakkers

Keyword(s):

Refractive Index ◽

High Refractive Index ◽

Fabry Perot

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Transition Metal Dichalcogenide Nanoantennas Lattice

MRS Advances ◽

10.1557/adv.2019.357 ◽

2019 ◽

Vol 4 (41-42) ◽

pp. 2283-2288 ◽

Cited By ~ 1

Author(s):

Viktoriia E. Babicheva

Keyword(s):

Refractive Index ◽

Transition Metal ◽

Near Infrared ◽

Building Blocks ◽

High Refractive Index ◽

Photonic Devices ◽

Transition Metal Dichalcogenide ◽

Optical Resonances ◽

Infrared Spectral ◽

Spectral Ranges

ABSTRACTHigh-index materials such as silicon and III-V compounds have recently gained a lot of interest as a promising material platform for efficient photonic nanostructures. Because of the high refractive index, nanoparticles of such materials support Mie resonances and enable efficient light control and its confinement at the nanoscale. Here we propose a design of nanostructure with multipole resonances where optical nanoantennas are made out of transition metal dichalcogenide, in particular, tungsten disulfide WS2. Transition metal dichalcogenide (TMDCs) possess a high refractive index and strong optical anisotropy because of their layered structure and are promising building blocks for next-generation photonic devices. Strong anisotropic response results in different components of TMDC permittivity and the possibility of tailoring nanostructure optical properties by choosing different axes and adjusting dimensions in design. The proposed periodic array of TMDC nanoantennas can be used for controlling optical resonances in the visible and near-infrared spectral ranges and engineering efficient ultra-thin optical components with nanoscale light confinement.

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Planar hot-electron photodetector utilizing high refractive index MoS2 in Fabry–Pérot perfect absorber

Nanotechnology ◽

10.1088/1361-6528/ab8325 ◽

2020 ◽

Vol 31 (27) ◽

pp. 274001 ◽

Cited By ~ 3

Author(s):

Yisong Zhu ◽

Peng Yu ◽

Eric Ashalley ◽

Tianji Liu ◽

Feng Lin ◽

...

Keyword(s):

Refractive Index ◽

High Refractive Index ◽

Perfect Absorber ◽

Hot Electron ◽

Fabry Perot

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Interferometric Determination of the Refractive Index of Liquids by Difference IR Spectroscopy

Applied Spectroscopy ◽

10.1366/0003702874868061 ◽

1987 ◽

Vol 41 (1) ◽

pp. 88-93 ◽

Cited By ~ 5

Author(s):

H. M. Heise

Keyword(s):

Refractive Index ◽

Ir Spectroscopy ◽

High Refractive Index ◽

The Other ◽

Liquid Sample ◽

Multiple Reflections ◽

Interference Fringes ◽

Fabry Perot ◽

Window Material

A simple interferometric determination for the refractive index of liquids in the infrared is presented. The transmittance spectra of the liquid sample are recorded with two cells. One cell is assembled with a window material of high refractive index, producing interference fringes from multiple reflections (Fabry-Perot etalon); the other cell yields negligible interference as it is constructed from window material with a refractive index matched to that of the sample. By absorbance subtraction it is possible to eliminate most of the absorbance features, and the resulting channel spectrum can be used for the refractive index determination without the use of iterations and Kramers-Kronig transformation. The limitations are given by a theoretical consideration for Lorentzian band shapes, and two experimental examples are presented.

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A New Mounting Medium of High Refractive Index

Scientific American ◽

10.1038/scientificamerican02131886-8429csupp ◽

1886 ◽

Vol 21 (528supp) ◽

pp. 8429-8430

Keyword(s):

Refractive Index ◽

High Refractive Index

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Accelerated Discovery of High-Refractive-Index Polyimides via First-Principles Molecular Modeling, Virtual High-Throughput Screening, and Data Mining

10.26434/chemrxiv.7670903.v1 ◽

2019 ◽

Author(s):

Mohammad Atif Faiz Afzal ◽

Mojtaba Haghighatlari ◽

Sai Prasad Ganesh ◽

Chong Cheng ◽

Johannes Hachmann

Keyword(s):

Data Mining ◽

Refractive Index ◽

High Throughput ◽

First Principles ◽

High Throughput Screening ◽

Large Scale ◽

Computational Study ◽

High Refractive Index ◽

Structural Features ◽

Learning Program

<div>We present a high-throughput computational study to identify novel polyimides (PIs) with exceptional refractive index (RI) values for use as optic or optoelectronic materials. Our study utilizes an RI prediction protocol based on a combination of first-principles and data modeling developed in previous work, which we employ on a large-scale PI candidate library generated with the ChemLG code. We deploy the virtual screening software ChemHTPS to automate the assessment of this extensive pool of PI structures in order to determine the performance potential of each candidate. This rapid and efficient approach yields a number of highly promising leads compounds. Using the data mining and machine learning program package ChemML, we analyze the top candidates with respect to prevalent structural features and feature combinations that distinguish them from less promising ones. In particular, we explore the utility of various strategies that introduce highly polarizable moieties into the PI backbone to increase its RI yield. The derived insights provide a foundation for rational and targeted design that goes beyond traditional trial-and-error searches.</div>

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