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1.
Origin of the Blue Luminescence in Porous Anodic Alumina Films Formed in Oxalic Acid Solutions 下载免费PDF全文
GAOTao MENGGuo-Wen ZHANGLi-De 《中国物理快报》2003,20(5):713-716
Photoluminescence spectra of porous anodic alumina(PAA) films formed in oxalic acid solutions show a blue emission band peaked around 470nm,in which the corresponding excitation bands locate at 248nm,304nm,and 360nm,respectively.With the help of ascertaining the mechanism of this blue luminescence,the roles of the oxalic ions on the optical properties of the PAA films was discussed by using optical absorption spectra.It is suggested that the oxalic impurities with different existing or distributing forms would play important roles on the optical properties of PAA films.The 470-nm blue luminescence band could be attributed to the incorporated oxalic impurities rather than the F^ centres existed in the PAA films formed in oxalic acid solutions. 相似文献
2.
V. G. Golubev A. V. Medvedev A. B. Pevtsov A. V. Sel'kin N. A. Feoktistov 《Physics of the Solid State》1999,41(1):137-142
Photoluminescence spectra of thin hydrogenated-silicon films having mixed amorphous-nanocrystalline phase composition have
been studied. Fabry-Perot interference was found to affect strongly the shape of the spectra. An analysis of the spectra made
with inclusion of interference corrections shows that only one emission band forms in the 0.6–1.0 μm region due to carrier
recombination at centers of the same type.
Fiz. Tverd. Tela (St. Petersburg) 41, 153–158 (January 1999) 相似文献
3.
The spectra of transmission and reflection are measured in the region of 0.4–2.5 μm on thin silver selenium indate films obtained
by means of pulse laser vaporization. The magnitudes of the refractive index and absorption coefficient are calculated. The
energies of interband transitions and the values of crystalline and spin-orbit splitting are determined. The experimental
results for the AgInSe2 films agree with the data for bulk crystals.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 4, pp. 512–514, July–August, 2000. 相似文献
4.
Study of white light emission from ZnS/PS composite system 总被引:1,自引:0,他引:1
ZnS films were deposited by pulsed laser deposition(PLD)on porous silicon(PS)substrates formed by electrochemical anodization of p-type(100)silicon wafer.The photoluminescence(PL)spectra of ZnS/PS composites were measured at room temperature.Under different excitation wavelengths,the relative integrated intensities of the red light emission from PS layers and the blue-green emission from ZnS films had different values.After samples were annealed in vacuum at different temperatures(200,300,and 400℃)for 30 min respectively,a new green emission located at around 550 nm appeared in the PL spectra of all ZnS/PS samples,and all of the ZnS/PS composites had a broad PL band(450-700 nm)in the visible region,exhibiting intensively white light emission. 相似文献
5.
Lei Lü 《中国光学快报(英文版)》2007,5(9)
ZnS films were deposited by pulsed laser deposition (PLD) on porous silicon (PS) substrates formed by electrochemical anodization of p-type (100) silicon wafer. The photoluminescence (PL) spectra of ZnS/PS composites were measured at room temperature. Under different excitation wavelengths, the relative integrated intensities of the red light emission from PS layers and the blue-green emission from ZnS films had different values. After samples were annealed in vacuum at different temperatures (200, 300, and 400 ℃) for 30 min respectively, a new green emission located at around 550 nm appeared in the PL spectra of all ZnS/PS samples, and all of the ZnS/PS composites had a broad PL band (450 - 700 nm) in the visible region, exhibiting intensively white light emission. 相似文献
6.
We have investigated the deposition of 91% ZrO2 − 9% Y2O3 thin films by a variety of sputtering techniques for the application as electrolytes in thin film solid oxide fuel cells.
The deposition by RF sputtering was accomplished by using an oxide target of the desired composition. The deposition rate
in these initial tests was limited to 0.5 μm/hr and the morphology of the film was substantially modified by deposition rate
and substrate temperature. Using DC magnetron sputtering we deposited metallic films from a metallic target with the desired
chemical composition. We introduced oxygen into the sputtering chamber to reactively deposit the desired 91% ZrO2 − 9% Y2O3 thin films; however, we encountered problems with target oxidation and growth rate reproducibility. We subsequently demonstrated
that controlled oxidation of the metallic films could result in adhering, non porous yttria stabilized zirconia films.
Paper presented at the 3rd Euroconference on Solid State Ionics, Teulada, Sardinia, Italy, Sept. 15–22, 1996 相似文献
7.
We have examined the process of redox dispersion of silver, using a solution simultaneously containing an oxidizing agent
(potassium ferricyanide) and a reducing agent (sodium borohydride). We have studied the changes over time in the Raman spectra
of the indicated solution when no silver particles are present and when such particles are added to the solution. We have
established that the silver particles have a catalytic effect on the reaction between potassium ferricyanide and sodium borohydride,
kinetically slowed down in alkaline medium. The original silver particles (1–20 μm) undergo redox dispersion as a result,
and Ag particles are formed with sizes 1–10 nm.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 2, pp. 182–186, March–April, 2006. 相似文献
8.
The absorption and fluorescence spectra and the lasing ability of aminocoumarin derivatives in thin polymer layers (0.5–0.8
μm) based on the copolymer methylmethacrylate with a methacrylic acid and the copolymer methylmethacrylate with glycidylmethacrylate
formed by coating of optically transparent glass substrates have been studied. It is found that the intensity of absorption
and luminescence as well as the lasing resource of coumarins are determined by the structure of the latter and by the nature
of the polymer medium. Compositions based on the copolymer methylmethacrylate with glycidylmethacrylate and aminocoumarin
derivatives with a fluorized methyl group at the 4th molecular position can be of interest in optical technologies (light
transformers, amplifiers).
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 4, pp. 464–467, July–August, 2005. 相似文献
9.
M. V. Bogdanovich A. I. Enzhievskii G. I. Ryabtsev V. V. Kuznetsova V. V. Mashko L. L. Teplyashin L. I. Burov A. G. Ryabtsev M. A. Shchemelev A. S. Kraskovskii 《Journal of Applied Spectroscopy》2006,73(4):546-550
Based on analysis of the laser emission spectra of borosilicophosphate glass, coactivated by Er3+ and Yb3+ ions, we have determined the structure of the Stark splitting of the luminescence band for the erbium ion in the 1.5 μm region
(the transition 4I13/2 → 4I15/2). In the wavelength interval 1532–1547 nm, we identified 12 sets of lines belonging to different types of optical centers
of predominantly cubic symmetry.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 4, pp. 483–487, July–August, 2006. 相似文献
10.
A. N. Obraztsov I. Yu. Pavlovskii H. Okushi H. Watanabe 《Physics of the Solid State》1997,39(10):1594-1598
Photoacoustic spectroscopy is used to study optical absorption in diamond powders and polycrystalline films. The photoacoustic
spectra of diamond powders with crystallite sizes in the range from ∼100 μm to 4 nm and diamond films grown by chemical vapor deposition (CVD) had a number of general characteristic features corresponding
to the fundamental absorption edge for light with photon energies exceeding the width of the diamond band gap (∼5.4 eV) and
to absorption in the visible and infrared by crystal-structure defects and the presence of non-diamond carbon. For samples
of thin (∼10 μm) diamond films on silicon, the photoacoustic spectra revealed peculiarities associated with absorption in the silicon substrate
of light transmitted by the diamond film. The shape of the spectral dependence of the amplitude of the photoacoustic signal
in the ultraviolet indicates considerable scattering of light specularly reflected from the randomly distributed faces of
the diamond crystallites both in the polycrystalline films and in the powders. The dependence of the shape of the photoacoustic
spectra on the light modulation frequency allows one to estimate the thermal conductivity of the diamond films, which turns
out to be significantly lower than the thermal conductivity of single-crystal diamond.
Fiz. Tverd. Tela (St. Petersburg) 39, 1787–1791 (October 1997) 相似文献
11.
P. K. Kashkarov B. V. Kamenev M. G. Lisachenko O. A. Shalygina V. Yu. Timoshenk M. Schmidt J. Heitmann M. Zacharias 《Physics of the Solid State》2004,46(1):104-108
The photoluminescence spectra and kinetics of both erbium-doped and undoped multilayer structures of quasi-ordered silicon
nanocrystals in a silicon dioxide matrix were studied. It was shown that the optical excitation energy of silicon nanocrystals
2–3 nm in size can be practically completely transferred to Er3+ ions in the oxide surrounding the nanocrystals, with its subsequent radiation at 1.5 μm. Possible reasons for the high excitation
efficiency of the Er3+ ions are discussed, and the conclusion is drawn that the F?rster mechanism is dominant in the energy transfer processes occurring
in these structures.
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Translated from Fizika Tverdogo Tela, Vol. 46, No. 1, 2004, pp. 105–109.
Original Russian Text Copyright ? 2004 by Kashkarov, Kamenev, Lisachenko, Shalygina, Timoshenko, Schmidt, Heitmann, Zacharias. 相似文献
12.
L. G. Samsonova N. S. Eremina V. A. Svetlichnyi T. N. Kopylova G. V. Maier N. S. Kobotaeva E. E. Sirotkina 《Journal of Applied Spectroscopy》2006,73(2):194-199
We have studied the spectral and lasing properties of 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM)
in polyepoxypropylcarbazole (PEPK), polybutylcarbazole (PBK), and polyvinylcarbazole (PVK) films when excited by emission
from a XeCl laser (λ = 308 nm) and the second harmonic of a YAGNd laser (λ = 532 nm). Stimulated emission was excited without
an external cavity in the traveling wave mode in films of thickness 0.5–0.8 μm, obtained by the centrifuging method.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 2, pp. 177–181, March–April, 2006. 相似文献
13.
Optical Transmission Spectra of Anodic Aluminum Oxide Membranes with a Dual Layer-by-Layer Structure 下载免费PDF全文
By adjusting the anodization voltage periodically in the process of electrochemical oxidation of Muminum and subsequent chemical etching, anodic aluminum oxide membranes with a dual periodic layer-by-layer structure are prepared. Optical transmission spectra analyses prove that the dip position is dependent on the thickness of the layer and can be easily adjusted by the anodization voltage according to the Bragg-Snell formula. This result implies that the position and width of the stop band and the pass band in the visible and near infrared wavelength region can be designed and prepared arbitrarily. It is expected that these kinds of anodic aluminum oxide membranes may find applications in the fabrication of various optical devices. 相似文献
14.
V. K. Zaitsev M. I. Fedorov O. A. Golikova V. M. Orlov 《Physics of the Solid State》2001,43(9):1637-1638
The absorption coefficient of α-AlB12 was measured on single crystal samples at T=300 K within a broad spectral region (0.6–25 μm). In the region of the transparency window (3–6 μm), the absorption coefficient
was measured in the temperature range from 165 to 650 K. An analysis of the experimental data shows that the energy spectrum
of local states in the α-AlB12 bandgap has certain features. It was established that a broad band of local states lies near the conduction band and that
a trap level is located at 0.11±0.02 eV from the top of the valence band.
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Translated from Fizika Tverdogo Tela, Vol. 43, No. 9, 2001, pp. 1573–1574.
Original Russian Text Copyright ? 2001 by Zaitsev, Fedorov, Golikova, Orlov.
Deceased. 相似文献
15.
We have investigated the regularities in forming the spectral characteristic of three-component polymeric-crystalline polytetrafluorethylene-Ge-LiF
interference systems in the wide IR spectral region 0.8–160 μm. The efficiency of suppressing short-wave radiation by structurally
asymmetric imerference systems consisting of polytetrafluorethylene and quasihomogeneous layers with a high refractive index
is shown. Two of this kind of three-layer systems are sufficient for suppressing background radiation within the wavelength
interval from the visible range to ∼35 μm owing to multiple reflection at the boundaries of elementary Ge and LiF layers that
form quasihomogeneous layers (λ ∼ 1.7–17.0 μm) and also due to absorption in the Ge (λ<1.7 μm) and Lif (λ ∼ 17–35 μm) layers.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No_ 3, pp. 379–381, May–June, 2000. 相似文献
16.
R. A. Babunts V. A. Vetrov I. V. Il’in E. N. Mokhov N. G. Romanov V. A. Khramtsov P. G. Baranov 《Physics of the Solid State》2000,42(5):829-835
The infrared luminescence of Er3+ ions has been studied in bulk crystals of silicon carbide 6H-SiC doped with erbium in the process of their growth. The erbium centers of different symmetry in the crystals are revealed
by the EPR technique. A number of intense luminescence bands of erbium ions are observed at a wavelength of about 1.54 μm.
The luminescence can be excited by the light with quantum energies above and below the band gap of SiC. It is found that the
luminescence exhibits unusual temperature behavior: as the temperature increases, the luminescence intensity abruptly rises
starting with 77 K, passes through a maximum at ∼240 K, and, in the vicinity of ∼400 K, decreases down to the values observed
at 77 K. The activation energies for the flare-up and quenching of the Er3+ luminescence are estimated at E
A
≈130 and ≈350 meV, respectively. The mechanisms of the flare-up and quenching of the Er3+ luminescence in SiC are discussed.
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Translated from Fizika Tverdogo Tela, Vol. 42, No. 5, 2000, pp. 809–815.
Original Russian Text Copyright ? 2000 by Babunts, Vetrov, Il’in, Mokhov, Romanov, Khramtsov, Baranov. 相似文献
17.
By means of spectroellipsometric technique, the dielectric functions of zinc telluride films, 0.1–1.7 μm thick, grown by molecular
beam epitaxy (MBE) are studied. The presence of a thin layer on the surface of the films, noticeably affecting the results
of measurements, is established. The analysis of spectra of the ZnTe dielectric functions available in the literature shows
that the surface layer was present in all samples studied, regardless of the method of preparation. It is shown that studying
the interference oscillations of the pseudodielectric function makes it possible to detect this layer and to correct properly
the measured spectra of the dielectric functions.
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Translated from Optika i Spektroskopiya, Vol. 92, No. 5, 2002, pp. 847–850.
Original Russian Text Copyright ? 2002 by Shvets, Yakushev. 相似文献
18.
Electroluminescence(EL)is observed from the Au/Si-rich SiO2 film/p-Si diodes,in which the Si-rich SiO2 films are scroed deliberately by a diamond tip.The EL intensity of the scroed diode annelaed at 800℃ is about 6 times of that of the unscored counterpart,The EL sectrum of the usscored diode could be decomposed into two Gaussian luminescence bands with peaks at about 1.83 and 2.23eV,while for the EL spectrum of the scored diode,an additional Gaussian band at about 3.0eV appears,and the 1.83-eV peak increases significantly in intensity,The photoluminescence(PL) spectrum of an unscored Si-rich SiO2 film has only one band peaking at about 1.48eV,whereas the Pl spectrum of the scored one has two bands at about 1.48 and 1.97eV.We consider that the high-density defect regions produced by the scoring provide new luminescence centres and become some types of nonradiative centres in the Si oxide layer,which thus result in changes of the EL and PL spectra. 相似文献
19.
S. Yu. Gus’kov M. O. Koshevoi V. B. Rozanov A. A. Rupasov A. S. Shikanov Yu. S. Kas’yanov 《JETP Letters》1996,64(7):502-508
Results are presented from an experimental investigation of the properties of the plasma produced by the action of a radiation
pulse at the second harmonic of a Nd laser, with average intensity ~5·1014 W/cm2 in the focal spot, on flat targets consisting of porous polypropylene (CH)x with an average density of 0.02 g/cm3 (close to the critical plasma density) and with ~50 μm pores. The properties of the laser plasma obtained with porous and
continuous targets are substantially different. The main differences are volume absorption of the laser radiation in the porous
material and much larger spatial scales of energy transfer. The experimentally measured longitudinal ablation velocity in
the porous material was equal to (1.5–3)·107 cm/s, which corresponds to a mass velocity of (3–6)·105 g/cm2· s, and the transverse (with respect to the direction of the laser beam) propagation velocity of the thermal wave was equal
to ~(1–2) ·107 cm/s. The spatial dimensions of the plasma plume were ~20–30μm. The plasma was localized in a 200–400μm region inside the
target.
Pis’ma Zh. éksp. Teor. Fiz. 64, No. 7, 462–467 (10 October 1996) 相似文献
20.
Yu. P. Rakovich A. L. Gurskii A. S. Smal’ A. A. Gladyshchuk Kh. Khamadi G. P. Yablonskii M. Khoiken 《Physics of the Solid State》1998,40(5):812-813
The exciton reflectance and photoluminescence spectra of epitaxial ZnSe/GaAs layers with a thickness of 2–4 μm are investigated
in the temperature range 10–120 K. It is shown that one of the causes of the formation of the doublet structure of the A
n=1 photoluminescence band is interference of the exciton radiation at the boundaries of the near-surface dead layer.
Fiz. Tverd. Tela (St. Petersburg) 40, 881–883 (May 1998) 相似文献