Dependence of the crystal lattice constant on isotopic composition: Theory and ab initio calculations for C, Si, and Ge

On the occasion of this special issue, we start by briefly outlining some of the history and future perspectives of the field of 3D metamaterials in general and 3D mechanical metamaterials in particular. Next, in the spirit of a specific example, we present our original numerical as well as experimental results on the phenomenon of acoustical activity, the mechanical counterpart of optical activity. We consider a three-dimensional chiral cubic mechanical metamaterial architecture that is different from the one that we have investigated in recent early experiments. We find even larger linear-polarization rotation angles per metamaterial crystal lattice constant than previously and a slower decrease of the effects towards the bulk limit.

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Characterization of crystal lattice constant and dislocation density of crack-free GaN films grown on Si(111)

Applied Surface Science ◽

10.1016/j.apsusc.2010.07.073 ◽

2010 ◽

Vol 257 (4) ◽

pp. 1161-1165 ◽

Cited By ~ 22

Author(s):

Jijun Xiong ◽

Jianjun Tang ◽

Ting Liang ◽

Yong Wang ◽

Chenyang Xue ◽

...

Keyword(s):

Dislocation Density ◽

Crystal Lattice ◽

Lattice Constant ◽

Crystal Lattice Constant

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Characterization of The Volcanic Rocks of Mount Sinabung, Simacem Village, Karo Regency, Conducted With XRD, SEM-EDX

Journal of Technomaterials Physics ◽

10.32734/jotp.v1i1.823 ◽

2019 ◽

Vol 1 (1) ◽

pp. 1-5

Author(s):

Perdinan Sinuhaji

Keyword(s):

Crystal Lattice ◽

Lattice Constant ◽

Elemental Analysis ◽

Volcanic Rocks ◽

Lattice Constants ◽

Crystal System ◽

Tetragonal Crystals ◽

Hexagonal Crystals ◽

Crystal Lattice Constant

The study of volcanic rocks characterization of Sinabung Volcano erupted on September 15, 2017. The volcanic rocks crystal system was performed with XRD, elemental analysis and microstructure with SEM-EDX. Volcanic rocks contain: Anorthite phase 87,11 (wt%), Triclinic crystal, lattice constant, a = 8.1742 Å, b = 12,844 Å, c = 14,204 Å; Quartz phase 2.26%, Hexagonal crystals, lattice constants, a = 4,799 Å, b = 4,799 Å, c = 5,379 Å; Cristobalite phase 7.72 (wt%), Tetragonal crystals, lattice constants a = 4,970 Å, b = 6,990 Å, c = 6,998 Å; Alunite phase 2.91 (wt%), Hexagonal crystals, lattice constants, a = 6,990 Å, b = 6,990 Å, c = 17,282 Å.

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AB-INITIO CALCULATIONS OF THE OPTICAL BAND GAP OF TiO2 THIN FILMS

International Journal of Nanoscience ◽

10.1142/s0219581x04002231 ◽

2004 ◽

Vol 03 (04n05) ◽

pp. 439-445 ◽

Cited By ~ 33

Author(s):

WILFRIED WUNDERLICH ◽

LEI MIAO ◽

MASAKI TANEMURA ◽

SAKAE TANEMURA ◽

PING JIN ◽

...

Keyword(s):

Thin Films ◽

Ab Initio Calculations ◽

Ab Initio ◽

Band Gap ◽

Lattice Constant ◽

Optical Band Gap ◽

Linear Increase ◽

Tio2 Thin Films ◽

Photocatalytic Application ◽

Experimental Values

Titanium dioxide has been extensively studied in recent decades for its important photocatalytic application in environmental purification. The search for a method to narrow the optical band gap of TiO 2 plays a key role for enhancing its photocatalytic application. The optical band gap of epitaxial rutile and anatase TiO 2 thin films deposited by helicon magnetron sputtering on sapphire and on SrTiO 3 substrates was correlated to the lattice constants. The optical band gap of 3.03 eV for bulk-rutile increased for the thin films to 3.37 on sapphire. The band gap of 3.20 eV for bulk-anatase increases to 3.51 on SrTiO 3. In order to interpret this expansion, ab-initio calculations were performed using the Vienna ab-initio software. The calculations for rutile as well anatase show an almost linear increase of the band gap width with decreasing volume or increasing lattice constant a. The calculated band gap fits well with the experimental values. The conclusion from these calculations is, in order to achieve a smaller band gap for both, rutile or anatase, the lattice constant c has to be compressed, and a has to be expanded.

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Relationship between electron work function and crystal lattice constant

2017 IEEE First Ukraine Conference on Electrical and Computer Engineering (UKRCON) ◽

10.1109/ukrcon.2017.8100327 ◽

2017 ◽

Cited By ~ 1

Author(s):

L. Korolevych ◽

A. Borisov ◽

H. Shevliakova

Keyword(s):

Crystal Lattice ◽

Work Function ◽

Lattice Constant ◽

Electron Work Function ◽

Crystal Lattice Constant

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Исследование характеристик сверхрешетки InGaAs/InAlGaAs для вертикально-излучающих лазеров спектрального диапазона 1300 nm

Журнал технической физики ◽

10.21883/jtf.2021.12.51767.240-21 ◽

2021 ◽

Vol 91 (12) ◽

pp. 2008

Author(s):

С.А. Блохин ◽

А.В. Бабичев ◽

А.Г. Гладышев ◽

Л.Я. Карачинский ◽

И.И. Новиков ◽

...

Keyword(s):

Crystal Lattice ◽

Quantum Wells ◽

Lattice Constant ◽

Current Density ◽

Lattice Mismatch ◽

Active Regions ◽

Cavity Surface ◽

Excitation Power Density ◽

Emitting Lasers ◽

Crystal Lattice Constant

X-ray structural analysis and photoluminescence spectroscopy techniques were used to study heterostructures based on InGaAs/InAlGaAs superlattice for active regions of 1300 nm range lasers grown by molecular beam epitaxy. It is shown that the grown heterostructures have a high crystal quality. The perpendicular lattice mismatch of the average crystal lattice constant of the InGaAs/InAlGaAs superlattice with respect to the crystal lattice constant of the InP substrate is estimated at ~ +0.01%. An analysis of the photoluminescence spectra made it possible to conclude that the contribution of Auger recombination is insignificant in the studied range of excitation power density. Studies of vertical-cavity surface-emitting lasers with an active region based on the InGaAs/InAlGaAs superlattice made it possible to estimate the gain coefficient at a level of 650 cm-1 for the standard logarithmic approximation of the dependence of the gain on the current density. The transparency current density of the laser was ~150 А/cm2, which is comparable to the record low values for the case of highly strained InGaAs-GaAs and InGaAsN-GaAs quantum wells in the spectral ranges of 1200 nm and 1300 nm, respectively.

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Characterization of crystal lattice constant and strain of GaN epilayers with different AlxGa1－xN and AlN buffer layers grown on Si(111)

Acta Physica Sinica ◽

10.7498/aps.55.2977 ◽

2006 ◽

Vol 55 (6) ◽

pp. 2977

Author(s):

Ding Zhi-Bo ◽

Yao Shu-De ◽

Wang Kun ◽

Cheng Kai

Keyword(s):

Crystal Lattice ◽

Lattice Constant ◽

Buffer Layers ◽

Aln Buffer ◽

Crystal Lattice Constant

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Density and Mechanical Strength of Ferrite for Inertial Gyroscope

Materials Science Forum ◽

10.4028/www.scientific.net/msf.546-549.2265 ◽

2007 ◽

Vol 546-549 ◽

pp. 2265-2268

Author(s):

Zhong Yu ◽

Zhong Wen Lan ◽

Ke Sun ◽

Yu Chen

Keyword(s):

Grain Size ◽

Fracture Surface ◽

Crystal Lattice ◽

Lattice Constant ◽

Bending Strength ◽

X Ray Diffraction ◽

X Ray ◽

Zn Ferrite ◽

Electronic Microscope ◽

Crystal Lattice Constant

The effects of NiO on density and mechanic strength of Mn-Zn ferrite used for inertial gyroscope were investigated by measurements of crystal lattice constant, Vickers hardness, bending strength. To investigate this further, powder of Mn-Zn ferrite was characterized by x-ray diffraction (XRD) and the fracture surface of Mn-Zn ferrite was checked by scanning electronic microscope (SEM). The investigation revealed that the substitution of Ni2+ modified crystal lattice constant and crystal grain size so that it caused crystal lattice constant of Mn-Zn ferrite to decline and crystal grain size to decrease, therefore it was useful to improve density and mechanic strength of Mn-Zn ferrite by this way. The results show that proper addition of NiO can bring higher density and more perfect mechanic strength of Mn-Zn ferrite used for inertial gyroscope.

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