Depth distributions of heavy ions in LiNbO3 and KTiOPO4 at tilted angle implantation

200 keV Hg and 1000 keV Xe ions were implanted into LiNbO3 and KTiOPO4 at a tilted angle. The depth distributions of Hg and Xe ions in LiNbO3 and KTiOPO4 were measured by Rutherford backscattering of MeV He ions. The experimental ion distributions are compared with the transport of ions in matter (TRIM'89) simulation. The result shows a slight difference in the peak position between the experimental and theoretical ion distribution, but the form of the experimental ion distribution is found to be in agreement with the theoretical one predicted by TRIM'89 except for a different width in the case of LiNbO3. The FWHM (full width at half maximum) of the experimental ion distribution is larger than the theoretical one given by TRIM'89 in the case of KTiOPO4. The lateral spreads obtained are compared using different calculation procedures.

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Resolution of X-Ray Rocking Curve Measurements Made with Finite Counting Statistics

International Journal of High Speed Electronics and Systems ◽

10.1142/s012915641550007x ◽

2015 ◽

Vol 24 (03n04) ◽

pp. 1550007 ◽

Cited By ~ 3

Author(s):

Tedi Kujofsa ◽

John E. Ayers

Keyword(s):

Peak Position ◽

Bragg Angle ◽

Full Width ◽

Half Maximum ◽

Peak Width ◽

Effective Number ◽

Rocking Curve ◽

X Ray ◽

Experimental Resolution ◽

Counting Statistics

We have analyzed the strain resolution of x-ray rocking curve profiles from measurements of the peak position and peak width made with finite counting statistics. In this work, we have considered x-ray rocking curves which may be Gaussian or Lorentzian in character and have analyzed the influence of the effective number of counts, full-width-at-half-maximum (FWHM) and the Bragg angle on the resolution. Often experimental resolution values are estimated on the order of 10−5 whereas this work predicts more sensitive values (10−9) with smaller FWHM and larger effective counts and Bragg angles.

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Surface Morphology of Ingap in the Ai-Free Pump Ld

MRS Proceedings ◽

10.1557/proc-440-287 ◽

1996 ◽

Vol 440 ◽

Author(s):

Ahn Goo Choo ◽

Seong Heon Kim ◽

Nam Heon Kim ◽

Oleg Laboutine ◽

Joon Sang Yu ◽

...

Keyword(s):

Surface Morphology ◽

Growth Parameters ◽

Peak Position ◽

Full Width ◽

Half Maximum ◽

Peak Wavelength ◽

Force Microscopy ◽

Atomic Force ◽

Pl Spectrum ◽

Reactor Pressure

AbstractWe have studied the effects of growth parameters and substrate orientations on InGaP quality using Normarski microscopy, photoluminescence (PL) spectrum and atomic force microscopy (AFM). The full width at half maximum (FWHNM) and peak position of PL spectrum were closely related with the surface morphology. The InGaP layers of narrower FWHM and shorter peak wavelength had smoother surface morphology. The InGaP layers grown on (100) substrates at the moderately low reactor pressure showed rougher surface than those on the tilted substrates. But the surface morphology was noticeably improved to be mirror-like at the lower reactor pressure. The surface morphology was inverted between the exact and tilted substrates in this reactor pressure. Furthermore, the samples grown on the tilted substrate exhibited rougher surface than the samples grown on the exact substrate. (111)B-misoriented growth surfaces had smoother than (111)A-misoriented surfaces.

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Spectroscopic Studies of Laser-Based Far-Ultraviolet Plasma Light Source

Applied Sciences ◽

10.3390/app11156919 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6919

Author(s):

Majid Masnavi ◽

Martin Richardson

Keyword(s):

Dense Plasma ◽

Wavelength Region ◽

Spectroscopic Studies ◽

Radiation Hydrodynamics ◽

Full Width ◽

Half Maximum ◽

Laser Plasmas ◽

Series Of Experiments ◽

Far Ultraviolet ◽

Radiation Conversion

A series of experiments is described which were conducted to measure the absolute spectral irradiances of laser plasmas created from metal targets over the wavelength region of 123–164 nm by two separate 1.0 μm lasers, i.e., using 100 Hz, 10 ns, 2–20 kHz, 60–100 ns full-width-at-half-maximum pulses. A maximum radiation conversion efficiency of ≈ 3%/2πsr is measured over a wavelength region from ≈ 125 to 160 nm. A developed collisional-radiative solver and radiation-hydrodynamics simulations in comparison to the spectra detected by the Seya–Namioka-type monochromator reveal the strong broadband experimental radiations which mainly originate from bound–bound transitions of low-ionized charges superimposed on a strong continuum from a dense plasma with an electron temperature of less than 10 eV.

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Time to peak and full width at half maximum in MR perfusion: valuable indicators for monitoring moyamoya patients after revascularization

Scientific Reports ◽

10.1038/s41598-020-80036-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Adam Huang ◽

Chung-Wei Lee ◽

Hon-Man Liu

Keyword(s):

Study Data ◽

Unknown Etiology ◽

Dynamic Susceptibility ◽

Full Width ◽

Half Maximum ◽

Mr Perfusion ◽

Dynamic Susceptibility Contrast ◽

Time To Peak ◽

Mr Perfusion Imaging ◽

Outcome Monitoring

AbstractMoyamoya disease (MMD) is a chronic, steno-occlusive cerebrovascular disorder of unknown etiology. Surgical treatment is the only known effective method to restore blood flow to affected areas of the brain. However, there are lack of generally accepted noninvasive tools for therapeutic outcome monitoring. As dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) is the standard MR perfusion imaging technique in the clinical setting, we investigated a dataset of nineteen pediatric MMD patients with one preoperational and multiple periodic DSC MRI examinations for four to thirty-eight months after indirect revascularization. A rigid gamma variate model was used to derive two nondeconvolution-based perfusion parameters: time to peak (TTP) and full width at half maximum (FWHM) for monitoring transitional bolus delay and dispersion changes respectively. TTP and FWHM values were normalized to the cerebellum. Here, we report that 74% (14/19) of patients improve in both TTP and FWHM measurements, and whereof 57% (8/14) improve more noticeably on FWHM. TTP is in good agreement with Tmax in estimating bolus delay. Our study data also suggest bolus dispersion estimated by FWHM is an additional, informative indicator in pediatric MMD monitoring.

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Time Dependence of γ/γ' Lattice Mismatch in Creep-Deformed Single Crystal Superalloy SC16 at 1173 K

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.3059 ◽

2007 ◽

Vol 539-543 ◽

pp. 3059-3063 ◽

Cited By ~ 2

Author(s):

G. Schumacher ◽

N. Darowski ◽

I. Zizak ◽

Hellmuth Klingelhöffer ◽

W. Chen ◽

...

Keyword(s):

Single Crystal ◽

Lattice Mismatch ◽

Lattice Misfit ◽

Peak Position ◽

Single Crystal Superalloy ◽

Tensile Creep ◽

Full Width ◽

X Ray Diffraction ◽

X Ray ◽

Time Period

The profiles of 001 and 002 reflections have been measured at 1173 K as a function of time by means of X-ray diffraction (XRD) on tensile-creep deformed specimens of single crystal superalloy SC16. Decrease in line width (full width at half maximum: FWHM) by about 7 % and increase in peak position by about 3x10-4 degrees was detected after 8.5x104 s. Broadening of the 002 peak profile indicated a more negative value of the lattice misfit after the same time period. The results are discussed in the context of the anisotropic arrangement of dislocations at the γ/γ’ interfaces during creep and their rearrangement during the thermal treatment at 1173 K.

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Preparation of highly c-axis oriented AlN thin films on Hastelloy tapes with Y2O3 buffer layer for flexible SAW sensor applications

Functional Materials Letters ◽

10.1142/s1793604716500235 ◽

2016 ◽

Vol 09 (02) ◽

pp. 1650023 ◽

Cited By ~ 2

Author(s):

Bin Peng ◽

Jianying Jiang ◽

Guo Chen ◽

Lin Shu ◽

Jie Feng ◽

...

Keyword(s):

Buffer Layer ◽

Smooth Surface ◽

Piezoelectric Coefficient ◽

Piezoelectric Properties ◽

Mean Square ◽

Full Width ◽

Half Maximum ◽

Sensor Applications ◽

Saw Sensor ◽

Y2o3 Buffer Layer

Highly c-axis oriented aluminum nitrade (AlN) films were successfully deposited on flexible Hastelloy tapes by middle-frequency magnetron sputtering. The microstructure and piezoelectric properties of the AlN films were investigated. The results show that the AlN films deposited directly on the bare Hastelloy substrate have rough surface with root mean square (RMS) roughness of 32.43[Formula: see text]nm and its full width at half maximum (FWHM) of the AlN (0002) peak is [Formula: see text]. However, the AlN films deposited on the Hastelloy substrate with Y2O3 buffer layer show smooth surface with RMS roughness of 5.46[Formula: see text]nm and its FWHM of the AlN (0002) peak is only [Formula: see text]. The piezoelectric coefficient d[Formula: see text] of the AlN films deposited on the Y2O3/Hastelloy substrate is larger than three times that of the AlN films deposited on the bare Hastelloy substrate. The prepared highly c-axis oriented AlN films can be used to develop high-temperature flexible SAW sensors.

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Research of the anti-resonance pulse forming network and its application in the Marx generator

Laser and Particle Beams ◽

10.1017/s0263034616000641 ◽

2016 ◽

Vol 34 (4) ◽

pp. 675-686 ◽

Cited By ~ 12

Author(s):

Z.-L. Pan ◽

J.-H. Yang ◽

X.-B. Cheng

Keyword(s):

Equivalent Circuit ◽

Rise Time ◽

Pulse Width ◽

Marx Generator ◽

Full Width ◽

Half Maximum ◽

Compact Structure ◽

Fall Time ◽

Pulse Forming Network ◽

Load Pulse

AbstractAn anti-resonance pulse forming network (PFN) has been designed, analyzed, and tested for its application in generating quasi-square pulses. According to the circuit simulations, a compact generator based on two/three-section network was constructed. Two-section network is applied in the generator due to its compact structure, while three-section network is employed for generating pulses with higher quality. When two-section network is applied in the generator, the full-width at half-maximum of the load pulse is 400 ns, at the same time, its rise time, flat top and fall time are 90, 180 and 217 ns, respectively. When the three-section network is applied with the same pulse width of the load pulse, the rise time of the output decreases to 60 ns, while the flat top increases to 240 ns and the fall time reduces to 109 ns. Meanwhile, this kind of network could be used to shape the output pulses of generators whose equivalent circuit is LC series discharge network, such as MARX generator, into quasi-square pulses. And the preliminary experiment demonstrates that anti-resonance network could work well on four-stage Marx generators. A sine pulse generated by the four-stage Marx generator is shaped into a quasi-square pulse with voltage of 11.8 kV and pulse width about 110 ns based on two-section anti-resonance network.

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Photoluminescence of Erbium-Diffused Silicon

MRS Proceedings ◽

10.1557/proc-422-81 ◽

1996 ◽

Vol 422 ◽

Author(s):

H. Horiguchi ◽

T. Kinone ◽

R. Saito ◽

T. Kimura ◽

T. Ikoma

Keyword(s):

Room Temperature ◽

Crystalline Silicon ◽

Luminescence Spectra ◽

Main Peak ◽

Silicon Substrates ◽

Annealing Atmosphere ◽

Full Width ◽

Half Maximum ◽

Strong Luminescence ◽

Fine Structures

AbstractErbium films are evaporated on crystalline silicon substrates and are thermally diffused into silicon in an Ar+02 or H2 flow. Very sharp Er3+-related luminescence peaks are observed around 1.54 μ m.The main peak as well as the fine structures of the luminescence spectra depend on the annealing atmosphere, suggesting different luminescence centers. The full width at half maximum (FWHM) of the main peaks is ≤ 0.5nm at 20K. Thermal diffusion with Al films on top of the Er films is found to increase the intensity of the Er3+-related peaks greatly. The temperature dependence between 20 K and room temperature is relatively small, and a strong luminescence is obtained at room temperature.

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Supershort avalanche electron beam generation in gases

Laser and Particle Beams ◽

10.1017/s0263034608000670 ◽

2008 ◽

Vol 26 (4) ◽

pp. 605-617 ◽

Cited By ~ 40

Author(s):

V.F. Tarasenko ◽

E.H. Baksht ◽

A.G. Burachenko ◽

I.D. Kostyrya ◽

M.I. Lomaev ◽

...

Keyword(s):

High Pressure ◽

Electron Beam ◽

Atmospheric Pressure ◽

Electron Beams ◽

Solid Angle ◽

Generation Mechanism ◽

Full Width ◽

Half Maximum ◽

Electron Beam Pulse ◽

Supershort Avalanche Electron Beam

AbstractThis paper reports on the properties of a supershort avalanche electron beam generated in the air or other gases under atmospheric pressure and gives the analysis of a generation mechanism of supershort avalanche electron beam, as well as methods of such electron beams registration. It is reported that in the air under the pressure of 1 atm, a supershort (<100 ps) avalanche electron beam is formed in the solid angle more than 2π steradian. The electron beam has been obtained behind a 45 µm thick Al-Be foil in SF6 and Xe under the pressure of 2 atm, and in He, under the pressure of about 15 atm. It is shown that in SF6 under the high pressure (>1 atm) duration (full width at half maximum) of supershort avalanche electron beam pulse is about 150 ps.

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Observation of strong excitonic magneto-chiral anisotropy in twisted bilayer van der Waals crystals

Nature Communications ◽

10.1038/s41467-021-22412-9 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Shoufeng Lan ◽

Xiaoze Liu ◽

Siqi Wang ◽

Hanyu Zhu ◽

Yawen Liu ◽

...

Keyword(s):

Time Reversal ◽

Room Temperature ◽

Photochemical Reactions ◽

Full Width ◽

Half Maximum ◽

A Value ◽

Device Applications ◽

Spectral Splitting ◽

Iron Garnet ◽

Spontaneous Magnetic Moment

AbstractThe interplay between chirality and magnetism generates a distinct physical process, the magneto-chiral effect, which enables one to develop functionalities that cannot be achieved solely by any of the two. Such a process is universal with the breaking of parity-inversion and time-reversal symmetry simultaneously. However, the magneto-chiral effect observed so far is weak when the matter responds to photons, electrons, or phonons. Here we report the first observation of strong magneto-chiral response to excitons in a twisted bilayer tungsten disulfide with the amplitude of excitonic magneto-chiral (ExMCh) anisotropy reaches a value of ~4%. We further found the ExMCh anisotropy features with a spectral splitting of ~7 nm, precisely the full-width at half maximum of the excitonic chirality spectrum. Without an externally applied strong magnetic field, the observed ExMCh effect with a spontaneous magnetic moment from the ferromagnetic substrate of thulium iron garnet at room temperature is favorable for device applications. The unique ExMCh processes provide a new pathway to actively control magneto-chiral applications in photochemical reactions, asymmetric synthesis, and drug delivery.

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