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1
Enhancement of coupling coefficient of laser plasma propulsion by water confinement
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Z.Y. Zheng , J. Zhang , Y. Zhang , F. Liu , M. Chen , X. Lu , Y.T. Li
Konu :
General Materials Science, General Chemistry
Yıl :
2006
Applied Physics A
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Water-confined laser ablation to enhance the coupling coefficient in laser plasma propulsion is proposed. It is found that the confinement of the plasma expansion due to the water layer leads to high absorption efficiency and therefore a high coupling coefficient of over 250 dyne/W is observed. This is an enhancement of over thirty times compared to that from direct ablation.
DOI : 10.1007/s00339-006-3714-x
Anahtar Kelimeler : Laser Pulse, Water Layer, Laser Energy, Target Surface, Laser Pulse Energy
ISSN: 0947-8396 1432-0630
Sayı: 4
Cilt: 85
Sayfa: 441-443
2
Wavelength multiplexing and tuning in nano-Ag/dielectric multilayers
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Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Gang Xu , Chun-Ming Huang , Qing Liang , Masato Tazawa , Ping Jin
Konu :
General Materials Science, General Chemistry
Yıl :
2008
Applied Physics A
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Multicolored optical active planes have been fabricated with magnetron sputter method coupled with selective masking technique. The plane is multilayer structured with Ag nanoparticles and TiO2 thin layer as the building blocks. It was found that the formed multilayer can be readily wavelength multiplexed by simply overlapping several nano-Ag/TiO2 layered structures, each of which may have different surface plasmon resonance wavelength. Unlike high order multiple resonances of large particles each of the multiplexing wavelengths in such a system is separately tunable. Importantly, it reveals that modification of the TiO2 layer thickness generates a fine tuning of the resonance wavelength.
DOI : 10.1007/s00339-008-4968-2
Anahtar Kelimeler : 61.46.+w, 81.07.-b, 36.40.GK, 42.70.-a, 81.15.Ef
ISSN: 0947-8396 1432-0630
Sayı: 3
Cilt: 94
Sayfa: 525-530
3
Equation of state of CaMnO3: a combined experimental and computational study
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Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Wojciech Paszkowicz , Scott M. Woodley , Paweł Piszora , Bohdan Bojanowski , Jarosław Piętosa , Yngve Cerenius , Stefan Carlson , Christine Martin
Konu :
General Materials Science, General Chemistry
Yıl :
2013
Applied Physics A
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Elastic properties of CaMnO3 are of primary importance in the science and technology of CaMnO3-based perovskites. From X-ray diffraction experiments performed at pressures up to 100 kbar using a diamond-anvil cell to hydrostatically compress our sample, a bulk modulus, K 0, of 1734(96) kbar was obtained after fitting parameters to the third-order Birch–Murnaghan equation of state. Mean field, semiclassical simulations predict, for the first time, the third-order equation-of-state parameters and show how the bulk modulus increases with pressure (the zero pressure value being 2062.1 kbar) and decreases with the extent of nonstoichiometry caused by the formation of oxygen vacancies. These trends are amplified for the shear modulus. A more accurate model that allows for the explicit reduction of Mn ions, or localization of excess electrons, yields qualitatively similar results. The experimental and calculated axial ratios show the same trends in their variation with rising pressure.
DOI : 10.1007/s00339-013-7577-7
Anahtar Kelimeler : Bulk Modulus, Axial Ratio, Pressure Transmit Medium, Double Exchange Interaction, Lower Atomic Density
ISSN: 0947-8396 1432-0630
Sayı: 4
Cilt: 112
Sayfa: 839-845
4
Wear-out and breakdown of rf sputtered Ta2O5 films on silicon
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
N. Novkovski , E. Atanassova
Konu :
General Materials Science, General Chemistry
Yıl :
2005
Applied Physics A
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The evolution of the gate voltage during the constant current stress of Ta2O5 films grown on silicon exhibits an additional decreasing region, compared to the case of SiO2 films. That phenomenon has been previously attributed to the thickness lowering of the ultrathin SiO2 interfacial layer naturally grown during the Ta2O5 deposition. Based on the previously proposed method of the evolution of the capacity in accumulation with the stress time, a simplified phenomenological model of capacitors in series was developed and employed as a tool for monitoring the degradation of the insulating film. In some cases breakdown events manifested by abrupt changes of the capacity in accumulation were observed, e.g., the case with the voltage on the silicon dioxide films. In other cases, saturation of the capacity in accumulation was detected, indicating continuous degradation of the SiO2 layer till its final destruction. The above effect was not observed in SiO2 films and can be peculiar for Ta2O5/SiO2 or similar stacked layers.
DOI : 10.1007/s00339-005-3233-1
Anahtar Kelimeler : Gate Voltage, Silicon Dioxide Layer, Conductive Path, Stress Time, Charge Trapping
ISSN: 0947-8396 1432-0630
Sayı: 7
Cilt: 81
Sayfa: 1455-1458
5
X-ray scattering for the atomic structure of a barium-induced Si(111)-3 $\times$ 2 surface
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
N.D. Kim , T.S. Kang , J.H. Je , H.J. Kim , D.Y. Noh , J.W. Chung
Konu :
General Materials Science, General Chemistry
Yıl :
2008
Applied Physics A
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We have investigated the atomic arrangement of a barium (Ba)-induced Si(111)-3×2 surface by using surface-sensitive synchrotron X-ray scattering. In-plane fractional-order reflections obtained from three rotational domains of 3×1 symmetry have been used to examine several competing structural models including the honeycomb-chain-channel (HCC) and the double-π-bonded chain (DπC) models. By fitting two different data sets, both the goodness-of-the fits χ2 and the residuum R-factor strongly favor the HCC over the DπC model. We conclude that a Ba-paired HCC structure with a \(\frac{1}{3}\) monolayer of Ba coverage best describes the Ba-induced 3×2 surface with a Ba-Ba interatomic spacing d = 1.93 Å.
DOI : 10.1007/s00339-007-4368-z
Anahtar Kelimeler : Atomic Arrangement, Interatomic Spacing, LEED Pattern, Rotational Domain, Patterson Function
ISSN: 0947-8396 1432-0630
Sayı: 1
Cilt: 91
Sayfa: 53-57
6
Elastic and piezoelectric fields around a quantum wire of zincblende heterostructures with interface elasticity effect
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Wei Ye , Yifei Liu
Konu :
General Materials Science, General Chemistry
Yıl :
2018
Applied Physics A
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This work formulates the solutions to the elastic and piezoelectric fields around a quantum wire (QWR) with interface elasticity effect. Closed-form solutions to the piezoelectric potential field of zincblende QWR/matrix heterostructures grown along [111] crystallographic orientation are found and numerical results of InAs/InP heterostructures are provided as an example. The piezoelectric potential in the matrix depends on the interface elasticity, the radius and stiffness of the QWR. Our results indicate that interface elasticity can significantly alter the elastic and piezoelectric fields near the interface. Additionally, when the elastic property of the QWR is considered to be anisotropic in contrary to the common isotropic assumption, piezoelectric potentials are found to be distinct near the interface, but the deviations are negligible at positions far away from the interface.
DOI : 10.1007/s00339-018-1722-2
ISSN: 0947-8396 1432-0630
Sayı: 4
Cilt: 124
7
Effect of annealing temperature on properties of yttrium-doped ZnO thin films grown by radio-frequency magnetron sputtering
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Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Johngeon Shin , Shinho Cho
Konu :
General Materials Science, General Chemistry
Yıl :
2019
Applied Physics A
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The effects of the rapid thermal annealing (RTA) temperature on the structural, morphological, optical, and electrical properties of yttrium-doped ZnO (YZO) thin films were investigated. The YZO thin films were prepared on glass substrates at a deposition temperature of 200 °C using radio-frequency magnetron sputtering. The as-grown thin films were annealed at various RTA temperatures for 30 min. Surface images showed that the crystalline grain sizes of the films increased with increasing RTA temperatures. A strong peak centered at 34.4°, which corresponds to diffraction from the (002) plane of ZnO, was observed for all the thin films annealed at different temperatures. The photoluminescence spectra of the YZO films was observed at approximately 411 nm, and the luminescence intensities showed an increasing tendency with increasing RTA temperature. As the RTA temperature was increased from 400 to 550 °C, the electron concentration and mobility decreased, and the resistivity increased. These results suggest that the properties of YZO thin films deposited by magnetron sputtering can be modulated by varying the RTA temperature.
DOI : 10.1007/s00339-019-3111-x
ISSN: 0947-8396 1432-0630
Sayı: 12
Cilt: 125
8
Formation of microbumps and nanojets on gold targets by femtosecond laser pulses
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
F. Korte , J. Koch , B.N. Chichkov
Konu :
General Materials Science, General Chemistry
Yıl :
2004
Applied Physics A
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Femtosecond laser-induced sub-wavelength microstructuring of a thin gold layer coated onto a quartz glass substrate is investigated. Formation of microbumps (microbubbles) and nanojets under single pulse laser irradiation is observed. Discussion of these effects and demonstration of their dependencies on the laser pulse energy and gold layer thickness are presented.
DOI : 10.1007/s00339-004-2590-5
Anahtar Kelimeler : Gold, Quartz, Laser Pulse, Layer Thickness, Laser Irradiation
ISSN: 0947-8396 1432-0630
Sayı: 4-6
Cilt: 79
Sayfa: 879-881
9
Efficient laser induced consolidation of nanoparticulate ZnO thin films with reduced thermal budget
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Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
M. Baum , S. Polster , M. P. M. Jank , I. Alexeev , L. Frey , M. Schmidt
Konu :
General Materials Science, General Chemistry
Yıl :
2012
Applied Physics A
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Layers of ZnO nanoparticles with thicknesses of about 40 nm were prepared on Si substrates. It was shown that UV laser irradiation is suitable for consolidation and significant densification of the ZnO particle layers under ambient conditions. Both experiments and simulations show that an underlying SiO2 particle layer has a beneficial effect in inhibiting heat transfer towards the substrate and thus enables the application of temperature-sensitive carrier substrates like polymer foils despite the extremely high melting temperature of ZnO.
DOI : 10.1007/s00339-012-6871-0
Anahtar Kelimeler : Buffer Layer, Laser Treatment, Pulse Laser Deposition, SiO2 Particle, Laser Annealing
ISSN: 0947-8396 1432-0630
Sayı: 2
Cilt: 107
Sayfa: 269-273
10
Hybrid reduced graphene oxide/TiO2/graphitic carbon nitride composites with improved photocatalytic activity for organic pollutant degradation
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Ping Lin , Haihua Hu , Huiru Lv , Zixuan Ding , Lingbo Xu , Degui Qian , Peng Wang , Jiaqi Pan , Chaorong Li , Can Cui
Konu :
General Materials Science, General Chemistry
Yıl :
2018
Applied Physics A
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The triple-component composites (rGO/TiO2/CN) were fabricated from the mixtures of the reduced graphene oxide (rGO) nanosheets, anatase TiO2 nanoparticles (NPs), and graphitic carbon nitride (g-C3N4) via simple mechanical stirring followed by calcination process. The rGO/TiO2/CN-0.75 sample with the optimal weight ratio exhibits improved photocatalytic activity, evidenced by methylene blue degradation, which is attributed to the synergistic effect of the incorporation of rGO and g-C3N4 with TiO2. The porous-layered structure of rGO and g-C3N4 encourages excellent dispersion of TiO2 NPs and consequently increases absorption sites and photocatalytic reaction sites. Meanwhile, the g-C3N4 expands visible-light absorption range and enhances the light harvest. Furthermore, rGO accelerates the photogenerated carrier separation and effectively suppresses charge recombination in the composites due to the excellent conductivity. The results provide a facile and promising strategy for enhancing the photocatalytic performance of TiO2-based composite photocatalysts.
DOI : 10.1007/s00339-018-1933-6
ISSN: 0947-8396 1432-0630
Sayı: 7
Cilt: 124
11
A three-dimensional ultra-broadband metamaterial absorber in terahertz region
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Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Xinyan Ling , Zhongyin Xiao , Xiaoxia Zheng , Jingyao Tang , Kaikai Xu
Konu :
General Materials Science, General Chemistry
Yıl :
2016
Applied Physics A
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Kaydet Alıntıla
In this paper, we proposed a three-dimensional metamaterial absorber with ultra-broadband in terahertz region. Compared with other three-layer structures, our structure is only composed of graphite film and a metal plate. The simulated results show that the metamaterial absorber can achieve an ultra-broadband absorption more than 90 % from 3 to 9 THz for either transverse electric or magnetic polarization wave at normal incidence. In addition, the absorption properties based on the oblique incidence and different polarization angles are also observed. A good absorption bandwidth can be kept when the incidence angle is up to 60°. Moreover, the absorber is polarization-insensitive with the polarization angle increase. Finally, the power loss density and surface current distributions at distinct resonance point are analyzed, which can demonstrate that the graphite plays an important role for the absorption of electromagnetic waves. We believe that the design idea of the three-dimensional metamaterial absorber maybe can extend to microwave, infrared or optical region.
DOI : 10.1007/s00339-016-0470-4
Anahtar Kelimeler : Polarization Angle, Electric Field Distribution, Polarization Wave, Resonance Point, Metamaterial Absorber
ISSN: 0947-8396 1432-0630
Sayı: 11
Cilt: 122
12
Fs-pulsed laser deposition of PbTe and PbTe/Ag thermoelectric thin films
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
A. Bellucci , E. Cappelli , S. Orlando , L. Medici , A. Mezzi , S. Kaciulis , R. Polini , D. M. Trucchi
Konu :
General Materials Science, General Chemistry
Yıl :
2014
Applied Physics A
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Kaydet Alıntıla
For the first time, thermoelectric thin films were fabricated by femtosecond pulsed laser deposition (fs-PLD) that represents a challenging technological solution for this application since it provides a correct film stoichiometry compared to the starting target, capability of native nanostructuring and a high deposition rate. In particular, this paper shows a preliminary work on PbTe and PbTe/Ag thin films deposited at different substrate temperatures by fs-PLD from a microcrystalline PbTe target. Structural, morphological and compositional characterizations of the deposited films were performed to demonstrate the formation of films composed by crystalline nanograins (about 35 nm size) and characterized by a correct stoichiometry. A remarkable deposition rate of 1.5 nm/s was evaluated. The electrical conductivity and the Seebeck coefficient (thermopower) were measured as a function of operating temperature to derive the thermoelectric power factor that was found to be less than a factor 2 with respect to the bulk materials. Finally, a discussion about the influence of compositional and structural properties of the deposited films on the related thermoelectric performances was presented.
DOI : 10.1007/s00339-014-8526-9
Anahtar Kelimeler : Power Factor, Pulse Laser Deposition, PbTe, Deposition Temperature, Seebeck Coefficient
ISSN: 0947-8396 1432-0630
Sayı: 1
Cilt: 117
Sayfa: 401-407
13
Effects of pulse laser duration and ambient nitrogen pressure in PLD of AlN
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
C. Ristoscu , E. Gyorgy , I.N. Mihailescu , A. Klini , V. Zorba , C. Fotakis
Konu :
General Materials Science, General Chemistry
Yıl :
2004
Applied Physics A
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Kaydet Alıntıla
AlN thin films with a thickness in the nanometer range were prepared by pulsed laser deposition technique. We investigated the effect of laser wavelength, pulse duration, and ambient gas pressure on the composition and morphology of the deposited films. In all experiments we used AlN targets. We worked with three laser sources generating pulses of 34 ns@248 nm (source A), 450 fs@248 nm (source B), and 50 fs@800 nm (source C). XRD, SEM, and profilometric measurements were performed on the obtained AlN thin films. We have demonstrated that duration of the laser pulse is an important parameter for the quality and performances of AlN structures obtained by pulsed laser deposition.
DOI : 10.1007/s00339-004-2857-x
Anahtar Kelimeler : Pulse Laser, Pulse Duration, Ambient Nitrogen, Pulse Laser Deposition, Laser Wavelength
ISSN: 0947-8396 1432-0630
Sayı: 4-6
Cilt: 79
Sayfa: 927-929
14
Fabrication and characterization of spherical micro semiconductor crystals by laser ablation method
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Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Tetsuya Shimogaki , Kota Okazaki , Kota Yamasaki , Koshi Fusazaki , Yasuaki Mizokami , Norihiro Tetsuyama , Mitsuhiro Higashihata , Hiroshi Ikenoue , Daisuke Nakamura , Tatsuo Okada
Konu :
General Materials Science, General Chemistry
Yıl :
2014
Applied Physics A
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Kaydet Alıntıla
We have been establishing the technique of fabricating spherical semiconductor microcrystals with suitable diameters for whispering gallery mode (WGM) lasing. Concretely, semiconductor microspheres were synthesized by ablating various semiconductor-sintered targets with focused pulsed laser at high fluences. In this report, dependences of fabricated zinc oxide (ZnO) microstructures on laser wavelengths were investigated. Lasing characteristics and photoluminescence of ZnO microspheres were determined, and photoluminescence of Sb-doped ZnO microspheres were determined. Additionally, it was also found that Sb-doped ZnO and aluminum nitride microspheres can be similarly synthesized. By developing this method, which does not require complex processing, it is expected that efforts in the application of WGM lasing are accelerated in many kinds of semiconductors.
DOI : 10.1007/s00339-014-8529-6
Anahtar Kelimeler : Aluminum Nitride, Whisper Gallery Mode, Excitation Power Density, Laser Ablation Method, Whisper Gallery Mode Resonator
ISSN: 0947-8396 1432-0630
Sayı: 1
Cilt: 117
Sayfa: 269-273
15
Electronic structure of low-pressure and high-pressure phases of silicon disulfide
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
D. I. Bletskan , V. V. Vakulchak , K. E. Glukhov
Konu :
General Materials Science, General Chemistry
Yıl :
2014
Applied Physics A
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Self-consistent density functional theory calculations of band spectra, densities of states as well as the spatial distribution of valence electron charge density were carried out for the low-pressure α-phase and the high-pressure β-phase of SiS2. Group-theoretical analysis performed for both phases enabled the symmetry of wave functions in a number of high-symmetry points of the Brillouin zone as well as the structure of valence band representations to be found. Based on the calculations of the band structure, the orthorhombic α-phase of SiS2 was determined to be an indirect-gap semiconductor with the band gap E gi = 2.44 eV (T 1 → X 8 transition), while the β-phase was shown to be direct gap with E gd = 2.95 eV (Г 3 → Г 2 transition). The calculated energy distribution of the total density of states in the valence band of α-SiS2 qualitatively and quantitatively correlates with the main experimental features of the X-ray photoelectron spectrum.
DOI : 10.1007/s00339-014-8584-z
Anahtar Kelimeler : Valence Band, Irreducible Representation, Brillouin Zone, Silicon Atom, SnSe2
ISSN: 0947-8396 1432-0630
Sayı: 3
Cilt: 117
Sayfa: 1499-1514
16
The effect of cesium metal clusters on the optical properties of cesium iodide thin films
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Kuldeep Kumar , P. Arun , Chhaya Ravi Kant , N. C. Mehra , Vincent Mathew
Konu :
General Materials Science, General Chemistry
Yıl :
2009
Applied Physics A
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Kaydet Alıntıla
Cesium metal clusters strongly affect the optical properties of cesium iodide thin films. The metal clusters are formed during film formation by thermal evaporation. The cesium cluster of 30–40 nm in the matrix of cesium iodide insulating thin films results in Surface Plasmon Resonance (SPR). The peak position of these SPR peaks showed a red shift. This was shown to be due to changes in the dielectric constant of CsI resulting from the strains in the films caused by the metal clusters themselves.
DOI : 10.1007/s00339-009-5532-4
Anahtar Kelimeler : Atomic Force Microscope, Surface Plasmon Resonance, Cesium, Atomic Force Microscope Image, Metal Cluster
ISSN: 0947-8396 1432-0630
Sayı: 1
Cilt: 99
Sayfa: 305-310
17
Structural, optical and electrical properties of sulfur-incorporated amorphous carbon films
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Latha Kumari , S. V. Subramanyam
Konu :
General Materials Science, General Chemistry
Yıl :
2008
Applied Physics A
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Kaydet Alıntıla
Amorphous carbon–sulfur (a-C:S) composite films were prepared by vapor phase pyrolysis technique. The structural changes in the a-C:S films were investigated by electron microscopy. A powder X-ray diffraction (XRD) study depicts the two-phase nature of a sulfur-incorporated a-C system. The optical bandgap energy shows a decreasing trend with an increase in the sulfur content and preparation temperature. This infers a sulfur incorporation and pyrolysis temperature induced reduction in structural disorder or increase in sp 2 or π-sites. The presence of sulfur (S 2p) in the a-C:S sample is analyzed by the X-ray photoelectron spectroscopy (XPS). The sp 3/sp 2 hybridization ratio is determined by using the XPS C 1s peak fitting, and the results confirm an increase in sp 2 hybrids with sulfur addition to a-C. The electrical resistivity variation in the films depends on both the sulfur concentration and the pyrolysis temperature.
DOI : 10.1007/s00339-008-4902-7
Anahtar Kelimeler : 81.05.Uw, 68.37.Hk, 79.60.-i, 73.50.-h
ISSN: 0947-8396 1432-0630
Sayı: 2
Cilt: 95
Sayfa: 343-349
18
Model for the hydrogen adsorption on carbon nanostructures
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
A. Züttel , P. Sudan , P. Mauron , P. Wenger
Konu :
General Materials Science, General Chemistry
Yıl :
2004
Applied Physics A
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Kaydet Alıntıla
The hydrogen sorption capacity of carbon nanostructures was for several years a very controversial subject. Theoretical models have been published demonstrating a great potential for a large hydrogen sorption capacity of carbon nanostructures. Here we present a simple empirical model where condensation of hydrogen as a monolayer at the surface of nanotubes as well as bulk condensation in the cavity of the tube is assumed. The maximum potential amount of hydrogen absorbed according to the model was calculated to be 2.28×10-3 mass % S[m2g-1]=3.0 mass % for the adsorption of a monolayer hydrogen at the surface. The condensation of hydrogen in the cavity of the tube leads to a potential absorption for single wall nanotubes starting at 1.5 mass % and increasing with the diameter of the tubes. The experimentally measured hydrogen capacity of the nanotube samples correlates with the B.E.T. specific surface area. The slope of the linear relationship is 1.5×10-3 mass %/m2g-1. Therefore, the extrapolated maximum discharge capacity of a carbon sample is 2 mass %. Furthermore, it can be concluded, that the hydrogen sorption mechanism is related to the surface of the sample, i.e. a surface adsorption process.
DOI : 10.1007/s00339-003-2412-1
Anahtar Kelimeler : Adsorption Process, Discharge Capacity, Hydrogen Adsorption, Maximum Discharge, Carbon Sample
ISSN: 0947-8396 1432-0630
Sayı: 7
Cilt: 78
Sayfa: 941-946
19
3D plasmonic transducer based on gold nanoparticles produced by laser ablation on silica nanowires
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
F. Gontad , A. P. Caricato , M. G. Manera , A. Colombelli , V. Resta , A. Taurino , M. Cesaria , C. Leo , A. Convertino , A. Klini , A. Perrone , R. Rella , M. Martino
Konu :
General Materials Science, General Chemistry
Yıl :
2016
Applied Physics A
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Kaydet Alıntıla
Silica two-dimensional substrates and nanowires (NWs) forests have been successfully decorated with Au nanoparticles (NPs) through laser ablation by using a pulsed ArF excimer laser, for sensor applications. A uniform coverage of both substrate surfaces with NPs has been achieved controlling the number of laser pulses. The annealing of the as-deposited particles resulted in a uniform well-defined distribution of spherical NPs with an increased average diameter up to 25 nm. The deposited samples on silica NWs forest present a very good plasmonic resonance which resulted to be very sensitive to the changes of the environment (ethanol/water solutions with increasing concentration of ethanol) allowing the detection of changes on the second decimal digit of the refractive index, demonstrating its potentiality for further biosensing functionalities.
DOI : 10.1007/s00339-016-0063-2
Anahtar Kelimeler : Surface Plasmon Resonance, Pulse Laser Deposition, Laser Shot, Full Width Half Maximum, Refractive Index Change
ISSN: 0947-8396 1432-0630
Sayı: 5
Cilt: 122
20
Controllable synthesis of TiO2 nanoflowers and their morphology-dependent photocatalytic activities
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Jinbo Ni , Juan Gao , Xianya Geng , Dandan He , Xiaoning Guo
Konu :
General Materials Science, General Chemistry
Yıl :
2017
Applied Physics A
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Different surface morphologies of TiO2 films were prepared through hydrothermal synthesis method on transparent fluorine-doped tin oxide (FTO) substrates by changing reaction temperatures. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and X-ray photoelectron spectrometer (XPS). As the hydrothermal temperatures increases, the surface morphologies of the TiO2 changes from nanorods (150 °C) to nanobuds (180 °C), and finally to nanoflowers (210 °C). Evolution of these structures are accompanied by great variations of optical properties and photocatalytic activities including a narrowing of band gap from 3.01 to 2.97 eV, increase of UV–visible absorption intensity and specific surface area, and photocatalytic degradation efficiencies from 88.18 to 95.56%. Under ultraviolet light (UV light) irradiation, the TiO2 nanoflowers exhibit significantly activity (95.56%) in degradation of methyl orange (MO) compared to commercial P25 (76.15%). The outstanding photocatalytic activity of the TiO2 nanoflowers can be attributed to the synergetic effect of much larger specific surface area, the larger content of oxygen vacancy, and higher intensity of absorption. These findings help to grow unique TiO2 films with desired structure and activities for photocatalyst applications.
DOI : 10.1007/s00339-017-0824-6
Anahtar Kelimeler : TiO2, Hydrothermal process, Crystal growth, Photocatalytic activity
ISSN: 0947-8396 1432-0630
Sayı: 3
Cilt: 123
21
Effect of small quantity of chromium on the electrical, magnetic and magnetocaloric properties of Pr0.7Ca0.3Mn0.98Cr0.02O3 manganite
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
A. Bettaibi , R. Mu2019nassri , A. Selmi , H. Rahmouni , K. Khirouni , N. Chniba Boudjada , A. Cheikhrouhou
Konu :
General Materials Science, General Chemistry
Yıl :
2016
Applied Physics A
Yayıncı Web Sitesi
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Kaydet Alıntıla
Structural, electrical and thermomagnetic properties of Pr0.7Ca0.3Mn0.98Cr0.02O3 were investigated. Sample was prepared by solid-state reaction method. X-ray diffraction revealed that the sample crystallizes in the orthorhombic system with Pnma space group. Electrical conductivity and complex impedance studies of Pr0.7Ca0.3Mn0.98Cr0.02O3 system are analyzed. The investigated compound exhibits a semiconductor behavior in the whole explored temperature range. From 100 to 206 K, the increase in DC conductance is more than two decade. At higher temperatures, the conductance varies slowly and a saturation region appears. The conduction mechanism is found to be governed by small polaron hopping process which is explained by the short range thermally activated energy. Conductance spectrum is well described by Jonsher law, and the temperature dependence of the frequency exponent confirms that conduction mechanism is governed by hopping process of the localized carriers. Using complex impedance analysis, the compound is modeled by an electrical equivalent circuit. Also, such analysis confirms the contribution of grain boundary to the transport properties. The substitution of Mn by 2 % Cr destroyed the charge order state observed in the parent compound and induced a ferromagnetic phase at low temperatures. For a magnetic field change of 5 T, the material shows a maximum magnetic entropy change |∆S max| = 2.69 J kg−1 K−1 with a full width at half maximum δ TFWHM = 145 K, and a relative cooling power RCP = 389 J kg−1. Pr0.7Ca0.3Mn0.98Cr0.02O3 material demonstrates potential proprieties to be used in electronic and thermal devices and as magnetic refrigerant.
DOI : 10.1007/s00339-016-9780-9
Anahtar Kelimeler : Manganite, Magnetic Applied Field, Conduction Mechanism, Magnetocaloric Effect, Magnetic Entropy Change
ISSN: 0947-8396 1432-0630
Sayı: 3
Cilt: 122
22
Growth and electric properties of (100)-oriented Mn-doped (Bi0.5Na0.5)TiO3-BaTiO3 thin film by pulsed laser deposition
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Chengchao Jin , Feifei Wang , Chung Ming Leung , Yanxue Tang , Tao Wang , Qirong Yao , Wangzhou Shi
Konu :
General Materials Science, General Chemistry
Yıl :
2013
Applied Physics A
Yayıncı Web Sitesi
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Kaydet Alıntıla
Mn-doped (Bi0.5Na0.5)TiO3-BaTiO3 (BNBMT) thin film with the composition near the morphotropic phase boundary was grown on (La0.6Sr0.4)CoO3-electroded SrTiO3 single-crystal substrate by using pulsed laser deposition method. Ascribed to the crystal structure and lattice similarity, (100)-oriented BNBMT film with pure single-phase perovskite structure was obtained through carefully controlling the growth conditions. Enhanced ferroelectric and dielectric properties were obtained with large remanent polarization P r of ∼21 μC/cm2, coercive field E c of ∼7.4 kV/mm and dielectric constant \(\varepsilon_{33}^{T}/\varepsilon_{0}\) of ∼750 at 1 kHz. The excellent global electrical properties of the BNBMT film are promising for environmentally friendly ferroelectric devices.
DOI : 10.1007/s00339-013-8014-7
Anahtar Kelimeler : Morphotropic Phase Boundary, Remanent Polarization, LaNiO3, Pulse Laser Deposition Method, Metal Organic Decomposition
ISSN: 0947-8396 1432-0630
Sayı: 4
Cilt: 115
Sayfa: 1375-1379
23
Dielectric relaxation in LaSrCo1−x Al x O4 ceramics
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Xiao Qiang Liu , Wen Zhi Yang , Chang Lin Song , Xiang Ming Chen
Konu :
General Materials Science, General Chemistry
Yıl :
2010
Applied Physics A
Yayıncı Web Sitesi
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Kaydet Alıntıla
Dielectric properties of LaSrCo1−x Al x O4 (x=0, 0.1, 0.3, and 0.5) ceramics were investigated in a broad frequency and temperature range. The AC conductivity decreased with the increasing Al concentration. Dielectric constant increased at lower frequency and decreased at higher frequency when the Al concentration increased from 0.1 to 0.3, then it decreased at all frequencies as the x value was 0.5. While the dielectric loss decreased first and then increased with the increasing Al concentration. There was one dielectric relaxation in the curve of temperature dependence of dielectric properties of LaSrCo0.7Al0.3O4 ceramics. The nonadiabatic small polaronic hopping process should contribute to the dielectric relaxation in the present ceramics. The AC conductivity increased in about one order of magnitude after annealing the sample in the oxygen atmosphere, and this should be attributed to the appearance of interstitial oxygen in the annealed sample.
DOI : 10.1007/s00339-010-5715-z
Anahtar Kelimeler : Dielectric Property, Dielectric Loss, Dielectric Relaxation, Interstitial Oxygen, Increase Aluminum Content
ISSN: 0947-8396 1432-0630
Sayı: 4
Cilt: 100
Sayfa: 1131-1135
24
Al-doped zinc oxide films grown by successive chemical solution deposition
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
A.E. Rakhshani
Konu :
General Materials Science, General Chemistry
Yıl :
2008
Applied Physics A
Yayıncı Web Sitesi
Tam Metin
Kaydet Alıntıla
Films of ZnO were grown and doped by the successive chemical solution deposition technique from a zincate solution containing aluminum (Al/Zn molar ratio in the range 2–10%). To our knowledge, this is the first report of its kind. A post-deposition heat treatment in argon (500 °C, 20 min) was performed for the activation of incorporated Al donors. Films were characterized by using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, optical transmittance, photoluminescence and Hall-effect measurement. Films with a resistivity 0.2 Ω cm, carrier concentration 1.2×1018 cm-3 and mobility 26 cm2/V s can be grown from a solution with Al/Zn = 10%. Further reduction in resistivity is plausible by using more heavily doped solutions and by the optimization of annealing parameters. Although the doping process does not change the films’ structure and surface morphology, it slightly lowers the optical transparency in the visible region and blue shifts the room-temperature photoluminescence peak to 378 nm.
DOI : 10.1007/s00339-008-4542-y
Anahtar Kelimeler : Kuwait, Chemical Solution Deposition, Zincate Solution, Zinc Hydroxide, Auret
ISSN: 0947-8396 1432-0630
Sayı: 2
Cilt: 92
Sayfa: 413-416
25
Dyadic Green’s function of a PEMC cylinder
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Majid Rasouli Disfani , Keivan Vafi , Mohammad Sadegh Abrishamian
Konu :
General Materials Science, General Chemistry
Yıl :
2011
Applied Physics A
Yayıncı Web Sitesi
Tam Metin
Kaydet Alıntıla
The dyadic Green’s function of a PEMC cylinder is derived with the aid of the principle of scattering superposition and Ohm–Rayleigh method. The PEMC boundary conditions are presented in dyadic form and it shows that how the impedance parameter of PEMC and cross-polarized fields appear in the Green’s function. The asymptotic expansions of the dyadic function is calculated in order to attain a closed form for the electrical field.
DOI : 10.1007/s00339-011-6248-9
Anahtar Kelimeler : Mixed Boundary Condition, Perfect Electric Conductor, Vector Wave Function, Rayleigh Method, Perfect Magnetic Conductor
ISSN: 0947-8396 1432-0630
Sayı: 3
Cilt: 103
Sayfa: 765-769
26
Development of confocal X-ray fluorescence (XRF) microscopy at the Cornell high energy synchrotron source
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
A.R. Woll , J. Mass , C. Bisulca , R. Huang , D.H. Bilderback , S. Gruner , N. Gao
Konu :
General Materials Science, General Chemistry
Yıl :
2006
Applied Physics A
Yayıncı Web Sitesi
Tam Metin
Kaydet Alıntıla
A confocal X-ray fluorescence microscope was built at the Cornell High Energy Synchrotron Source (CHESS) to obtain compositional depth profiles of historic paintings. The microscope consists of a single-bounce, borosilicate monocapillary optic to focus the incident beam onto the painting and a commercial borosilicate polycapillary lens to collect the fluorescent X-rays. The resolution of the microscope was measured by scanning a variety of thin metal films through this confocal volume while monitoring the fluorescence signal. The capabilities of the technique were then probed using test paint microstructures with up to four distinct layers, each having a thickness in the range of 10–80 microns. Results from confocal XRF were compared with those from stand-alone XRF and visible light microscopy of the paint cross-sections. A large area, high-resolution scanner is currently being built to perform 3D scans on moderately sized paintings.
DOI : 10.1007/s00339-006-3513-4
Anahtar Kelimeler : Incident Beam, Depth Resolution, Instrumental Resolution, Confocal Volume, Compositional Depth Profile
ISSN: 0947-8396 1432-0630
Sayı: 2
Cilt: 83
Sayfa: 235-238
27
Improvement of ammonia sensing properties of poly(pyrrole)–poly (n-methylpyrrole) composite by ion irradiation
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
S. B. Kadam , K. Datta , P. Ghosh , A. B. Kadam , P. W. Khirade , V. Kumar , R. G. Sonkawade , A. B. Gambhire , M. K. Lande , M. D. Shirsat
Konu :
General Materials Science, General Chemistry
Yıl :
2010
Applied Physics A
Yayıncı Web Sitesi
Tam Metin
Kaydet Alıntıla
In the present investigation we have electrochemically synthesized polypyrrole–poly (n-methylpyrrole) composite film with optimized process parameters (viz. concentration of monomers and dopant, applied current density, deposition time, pH of electrolyte etc.) on platinum substrate. The composite film of polypyrrole–poly (n-methylpyrrole) was subjected to electrical, spectral and morphological characterizations and its sensing response to various concentration of ammonia was also studied. Later, the synthesized composite films were irradiated under high vacuum (∼5×10−6 Torr) at room temperature with 85 MeV O7+ ion beam at various fluences from 1×105 to 1×107 ions/cm2. We have observed remarkable improvements in electrical and morphological properties suitable for gas-sensing applications. The irradiated composite film was evaluated for the sensing of various concentrations of ammonia and excellent improvement in terms of sensitivity, lower detection limit and response time was observed.
DOI : 10.1007/s00339-010-5705-1
Anahtar Kelimeler : Pyrrole, Composite Film, Optimize Process Parameter, Applied Current Density, Excellent Improvement
ISSN: 0947-8396 1432-0630
Sayı: 4
Cilt: 100
Sayfa: 1083-1088
28
Effects of chemical and biological warfare remediation agents on the materials of museum objects
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
C. Solazzo , D. Erhardt , F. Marte , D. von Endt , C. Tumosa
Konu :
General Materials Science, General Chemistry
Yıl :
2004
Applied Physics A
Yayıncı Web Sitesi
Tam Metin
Kaydet Alıntıla
In the fall of 2001, anthrax-contaminated letters were sent to public figures in the United States. Chemical and radiation treatments were employed to decontaminate exposed buildings, objects, and materials. These treatments are effective, but potentially damaging to exposed objects and materials. The recommended surface chemical treatments include solutions, gels, and foams of oxidizing agents such as peroxides or chlorine bleaching agents. Such oxidizing agents are effective against a wide range of hazardous chemical and biological agents. Knowing how these reagents affect various substrates would help to anticipate and to minimize any potential damage. We are examining the effects on typical museum materials of reagents likely to be used, including hydrogen peroxide, sodium hypochlorite, and potassium peroxymonosulfate. Results so far show significant changes in a number of materials. Surface corrosion was observed on metals such as copper, silver, iron, and brass. Color changes occurred with at least one reagent in about one-fourth of the dyed fabric swatches tested, and about half of the inks. Samples of aged yellowed paper are bleached. Effects varied with both the substrate and the tested reagent. The observed changes were generally less drastic than might have been expected. Enough materials were affected, though, to preclude the use of these reagents on museum objects unless no less drastic alternative is available. It appears that many objects of lesser intrinsic value can be treated without severe loss of properties or usefulness. For example, most documents should remain legible if the appropriate reagent is used. This work will provide a basis for determining which treatment is most appropriate for a specific situation and what consequences are to be expected from other treatments.
DOI : 10.1007/s00339-004-2511-7
Anahtar Kelimeler : Xylose, NaOCl, Oxone, Sodium Hypochlorite, Sodium Hypochlorite Solution
ISSN: 0947-8396 1432-0630
Sayı: 2
Cilt: 79
Sayfa: 247-252
29
Photoassisted chemical solution deposition method for fabricating uniformly epitaxial VO2 films
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Masami Nishikawa , Tomohiko Nakajima , Toshiya Kumagai , Takeshi Okutani , Tetsuo Tsuchiya
Konu :
General Materials Science, General Chemistry
Yıl :
2010
Applied Physics A
Yayıncı Web Sitesi
Tam Metin
Kaydet Alıntıla
Epitaxial VO2 films were prepared on the TiO2 (001) substrates by the excimer-laser-assisted metal–organic deposition (ELAMOD). The quality of the epitaxial films obtained by irradiation with a KrF laser was found to be affected by the film structure obtained after preheating at 500 or 300°C. When the films containing crystal domains, which were obtained by preheating at 500°C, were irradiated with the laser at room temperature under a base pressure of 250 Pa, epitaxial and polycrystalline VO2 phases were simultaneously formed. In contrast, when the amorphous films containing organic components, which were obtained by preheating at 300°C, were irradiated with the laser at room temperature in air, a single phase of epitaxial VO2 was formed. By using thermal simulations, we determined that the formation of the epitaxial phase was affected both by the temperature distribution within the film during the laser irradiation and by the laser intensity at the interface between the substrate and the film. The latter factor is considered to play a role in the nucleation of crystallization, causing the epitaxial phase to form preferentially compared to the polycrystalline phase in the amorphous matrix of the films. These results indicate that the ELAMOD process is effective for the fabrication of epitaxial VO2 films at low temperature.
DOI : 10.1007/s00339-010-5799-5
Anahtar Kelimeler : Laser Irradiation, Amorphous Matrix, Substrate Interface, Thermal Simulation, Chemical Solution Deposition
ISSN: 0947-8396 1432-0630
Sayı: 1
Cilt: 100
Sayfa: 297-303
30
Thermally chargeable supercapacitor working in a homogeneous, changing temperature field
Dergi Makalesi

Dergi Makalesi
Kaynak :
Springer Link
Dergi:
Applied Physics A
Yazar(lar) :
Hyuck Lim , Yang Shi , Yu Qiao
Konu :
General Materials Science, General Chemistry
Yıl :
2016
Applied Physics A
Yayıncı Web Sitesi
Tam Metin
Kaydet Alıntıla
A thermally chargeable supercapacitor (TCS) system is developed to harvest electrical energy from a uniform temperature field of a changing low-grade heat source. Without any temperature gradient, the TCS absorbs heat when temperature rises and releases electricity during discharging. As temperature decreases, the system configuration returns to the initial condition, so that the thermal-to-electrical energy conversion can be continuously conducted. With a nickel-coated carbon nanotube or nanoporous carbon-based electrode, the thermal sensitivity and the electrode surface area are enhanced simultaneously, leading to a high output voltage around 100–160 mV and a high specific energy of 600–1800 mJ per gram of electrode material in each thermal cycle, with a mild temperature range of ~50 °C.
DOI : 10.1007/s00339-016-9981-2
Anahtar Kelimeler : Gluconic Acid, Thermal Sensitivity, Organic Rankine Cycle, Nanoporous Carbon, Electrode Surface Area
ISSN: 0947-8396 1432-0630
Sayı: 4
Cilt: 122

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