scholarly journals InPBi Quantum Dots for Super-Luminescence Diodes

Nanomaterials ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 705 ◽  
Author(s):  
Liyao Zhang ◽  
Yuxin Song ◽  
Qimiao Chen ◽  
Zhongyunshen Zhu ◽  
Shumin Wang
Keyword(s):  
Quantum Confinement ◽  
Room Temperature ◽  
Light Emission ◽  
Wide Spectrum ◽  
Active Material ◽  
Low Light ◽  
Center Wavelength ◽  
Emission Efficiency ◽  
Spatial Size ◽  
Lattice Matched

InPBi thin film has shown ultra-broad room temperature photoluminescence, which is promising for applications in super-luminescent diodes (SLDs) but met problems with low light emission efficiency. In this paper, InPBi quantum dot (QD) is proposed to serve as the active material for future InPBi SLDs. The quantum confinement for carriers and reduced spatial size of QD structure can improve light emission efficiently. We employ finite element method to simulate strain distribution inside QDs and use the result as input for calculating electronic properties. We systematically investigate different transitions involving carriers on the band edges and the deep levels as a function of Bi composition and InPBi QD geometry embedded in InAlAs lattice matched to InP. A flat QD shape with a moderate Bi content of a few percent over 3.2% would provide the optimal performance of SLDs with a bright and wide spectrum at a short center wavelength, promising for future optical coherence tomography applications.

Control of and Mechanisms for Room Temperature Visible light Emission from Silicon Nanostructures in SiO2 formed by Si+ Ion Implantation

1994 ◽  
Vol 358 ◽  
Author(s):  
T. Komoda ◽  
J.P. Kelly ◽  
A. Nejm ◽  
K.P. Homewood ◽  
P.L.F Hemment ◽  
...  
Keyword(s):  
Quantum Confinement ◽  
Room Temperature ◽  
Light Emission ◽  
Silicon Nanostructures ◽  
Two Phase ◽  
Population Distributions ◽  
Si Nanocrystals ◽  
Induced Defects ◽  
Irradiation Induced Defects ◽  
Si Ion Implantation

ABSTRACTImplantation of Si+ ions into thermal oxides grown on silicon has been used to synthesise a two phase structure consisting of Si nanocrystals in a SiO2 matrix. Various processing conditions have been used in order to modify the size and population distributions of the Si inclusions. Photoluminescence spectra have been recorded from samples annealed in nitrogen, forming gas and oxygen. Both red and blue shifts of the luminescence peaks have been observed. It is concluded that the photoluminescence is a consequence of the effects of quantum confinement but is also dependent on the presence of irradiation-induced defects or Si/SiO2 interface states.

scholarly journals Transient Luminous Events, into the Stratosphere and the Mesosphere, observed during violent thunderstorms lightning, are explained thanks to laboratory jets of photons in air, occuring during emission of Gravitational Quanta

2021 ◽  
Vol 8 (5) ◽  
pp. 261-281
Author(s):  
Claude POHER ◽  
Danielle POHER
Keyword(s):  
Electric Fields ◽  
Room Temperature ◽  
Light Emission ◽  
Active Material ◽  
Quantum Model ◽  
Electric Discharges ◽  
Natural Graphite ◽  
Transient Luminous Events ◽  
Temperature And Pressure ◽  
Bright Emission

Abstract : A Gravitational field emitter, as we patented in 2006, is composed of an “active” material squeezed between two metallic electrodes. The active material is superconducting, with conductive or insulating grains added inside, to get local electric fields during brief electric discharges made into that emitter. Along such a discharge, the emitter propels itself, by anisotropic re-emission of interacting Gravitational Quanta. These emitted quanta accelerate distant matter particles placed along their trajectory. With early YBCO superconducting material emitters, cooled down by liquid nitrogen, we observed systematically a bright emission of light into the bath. This light emission is caused by nitrogen molecules’ ionization by gravitational quanta push. In 2012, the partial superconducting behavior of natural Graphite, at room temperature, was discovered, so we built new emitters from Graphite. These shown the same propelling effect as the early ones made of YBCO, with a lower performance. Here we record and discuss light emission in the form of jets of photons, in air, at room temperature, and pressure, during strong electric discharges into Graphite based emitters. These results enhance the confirmation of predictions from our theoretical Quantum model of Inertia and Gravitation. They explain also the enigmatic Transient Luminous Events observed in the atmosphere over thunderstorms clouds.  

scholarly journals GaAs-Based InPBi Quantum Dots for High Efficiency Super-Luminescence Diodes

2019 ◽  
Vol 20 (23) ◽  
pp. 6001
Author(s):  
Liyao Zhang ◽  
Yuxin Song ◽  
Qian Gong
Keyword(s):  
Strain Distribution ◽  
Photoluminescence Spectrum ◽  
Room Temperature ◽  
High Efficiency ◽  
Light Emission ◽  
Band Alignment ◽  
Potential Candidate ◽  
The Finite Element Method ◽  
Emission Efficiency ◽  
Broad Emission

InPBi exhibits broad and strong photoluminescence at room temperature, and is a potential candidate for fabricating super-luminescence diodes applied in optical coherence tomography. In this paper, the strained InPBi quantum dot (QD) embedded in the AlGaAs barrier on a GaAs platform is proposed to enhance the light emission efficiency and further broaden the photoluminescence spectrum. The finite element method is used to calculate the strain distribution, band alignment and confined levels of InPBi QDs. The carrier recombinations between the ground states and the deep levels are systematically investigated. A high Bi content and a flat QD shape are found preferable for fabricating super-luminescence diodes with high efficiency and a broad emission spectrum.

InAs/InGaAs quantum dots confined by InAlAs barriers for enhanced room temperature light emission: Photoelectric properties and deep levels

2021 ◽  
Vol 238 ◽  
pp. 111514
Author(s):  
Sergii Golovynskyi ◽  
Oleksandr I. Datsenko ◽  
Luca Seravalli ◽  
Giovanna Trevisi ◽  
Paola Frigeri ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Room Temperature ◽  
Light Emission ◽  
Deep Levels ◽  
Photoelectric Properties

GalnAsSb Materials for Thermophotovoltaics

1996 ◽  
Vol 450 ◽  
Author(s):  
C. A. Wang ◽  
G. W. Turner ◽  
M. J. Manfra ◽  
H. K. Choi ◽  
D. L. Spears
Keyword(s):  
Room Temperature ◽  
Molecular Beam ◽  
Hole Concentration ◽  
Organometallic Vapor Phase Epitaxy ◽  
Room Temperature Photoluminescence ◽  
P Type ◽  
First Time ◽  
Lattice Matched ◽  
Comparable Quality ◽  
Peak Emission

ABSTRACTGai1−xInxASySb1-y (0.06 < x < 0.18, 0.05 < y < 0.14) epilayers were grown lattice-matched to GaSb substrates by low-pressure organometallic vapor phase epitaxy (OMVPE) using triethylgallium, trimethylindium, tertiarybutylarsine, and trimethylantimony. These epilayers have a mirror-like surface morphology, and exhibit room temperature photoluminescence (PL) with peak emission wavelengths (λP,300K) out to 2.4 μm. 4K PL spectra have a full width at half-maximum of 11 meV or less for λP,4K < 2.1 μm (λP,300K = 2.3 μm). Nominally undoped layers are p-type with typical 300K hole concentration of 9 × 1015 cm−3 and mobility ∼ 450 to 580 cm2/V-s for layers grown at 575°C. Doping studies are reported for the first time for GalnAsSb layers doped n type with diethyltellurium and p type with dimethylzinc. Test diodes of p-GalnAsSb/n-GaSb have an ideality factor that ranges from 1.1 to 1.3. A comparison of electrical, optical, and structural properties of epilayers grown by molecular beam epitaxy indicates OMVPE-grown layers are of comparable quality.

A theoretical model describing the light emission efficiency of single-crystal scintillators in the diagnostic energy range

2009 ◽  
Vol 4 (06) ◽  
pp. P06016-P06016 ◽  
Author(s):  
A Petropoulou ◽  
N Kalyvas ◽  
I Kandarakis ◽  
I Valais ◽  
G S Panayiotakis
Keyword(s):  
Theoretical Model ◽  
Energy Range ◽  
Single Crystal ◽  
Light Emission ◽  
Emission Efficiency

scholarly journals Synthesis and Characterisation of Thin Films of Bismuth Triiodide for Semiconductor Radiation Detectors

2014 ◽  
Vol 2014 ◽  
pp. 1-3 ◽  
Author(s):  
Alka Garg ◽  
Monika Tomar ◽  
Vinay Gupta
Keyword(s):  
Thin Films ◽  
Absorption Coefficient ◽  
Room Temperature ◽  
Active Material ◽  
Visible Region ◽  
Radiation Detectors ◽  
Radiation Absorption ◽  
X Rays ◽  
X Ray ◽  
Bismuth Iodide

Bismuth iodide is a potentially active material for room temperature radiation detector, as it is well reported in the literature that it has both wide energy band gap and high atomic absorption coefficient. Crystalline films of high atomic number and high radiation absorption coefficient can absorb the X-rays and convert them directly into electrical charges which can be read by imaging devices. Therefore, it was proposed to grow thin films of Bismuth iodide on glass substrate using thermal evaporation technique in vacuum to avoid the inclusion of impurities in the films. The structural studies of the films were carried out using XRD and optical absorption measurement was carried out in the UV/VIS region using spectrophotometer. All Bismuth iodide films grown at room temperature are polycrystalline and show X-ray diffraction peaks at angles reported in research papers. The optical transmission spectra of BiI3 films show a high transmission of about 80% in visible region with a sharp fall near the fundamental absorption at 650 nm. Resistivity of the as-grown film was found to be around 1012 ohm-cm suitable value for X-ray detection application. Films were subjected to scanning electron microscopy to study the growth features of both as-grown and annealed films.

Thermal Strain Study of Almost Lattice-Matched Epitaxial InuGa1-uAs1-vP1-v Films on InP(100) Substrates

1989 ◽  
Vol 160 ◽  
Author(s):  
G. Bai ◽  
M-A. Nicolet ◽  
S.-J. Kim ◽  
R.G. Sobers ◽  
J.W. Lee ◽  
...  
Keyword(s):  
Room Temperature ◽  
Epitaxial Film ◽  
Lattice Mismatch ◽  
Thermal Strain ◽  
Growth Direction ◽  
Epitaxial Films ◽  
Double Crystal ◽  
X Ray ◽  
Lattice Matched ◽  
Coherent Interfaces

AbstractSingle layers of ~ 0.5µm thick InuGa1-uAs1-vPv (0.52 < u < 0.63 and 0.03 < v < 0.16) were grown epitaxially on InP(100) substrates by liquid phase epitaxy at ~ 630°C. The compositions of the films were chosen to yield a constant banndgap of ~ 0.8 eV (λ = 1.55 µm) at room temperature. The lattice mismatch at room temperature between the epitaxial film and the substrate varies from - 4 × 10-3 to + 4 × 10-3. The strain in the films was characterized in air by x-ray double crystal diffractometry with a controllable heating stage from 23°C to ~ 700°C. All the samples have an almost coherent interfaces from 23°C to about ~ 330°C with the lattice mismatch accomodated mainly by the tetragonal distortion of the epitaxial films. In this temperature range, the x-ray strain in the growth direction increases linearly with temperature at a rate of (2.0 ± 0.4) × 10-6/°C and the strain state of the films is reversible. Once the samples are heated above ~ 300°C, a significant irreversible deterioration of the epitaxial films sets in.

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