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Temperature dependence of photoluminescence peaks of porous silicon structures

Physics Conference Series 61, (2007) 1231-1235. [5] M. J. Estes and G. Moddel, Phys. Rev. B 54 (20), (1996) 14 633-14 642. [6] M. J. Estes and G. Moddel, Appl. Phys. Lett. 68 (13), 25 March 1996, 1814 - 1816. [7] A. S. Lenshin, V. M. Kashkarov, S. Y. Turishchev, M. Smirnov and E. Domashevskaya, “Influence of Natural Aging on the Photoluminescence of Porous Silicon”, Technical Physics , vol. 57, no. 2, 2012, 305-307. [8] N. E. Korsunskaya, T. R. Stara, L. Yu. Khomenkova, K. V. Svezhentsova, N. N. Melnichenko and F. F. Sizov, “The nature of

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Effect of lead salts on phase, morphologies and photoluminescence of nanocrystalline PbMoO4 and PbWO4 synthesized by microwave radiation

) equipped with energy dispersive X-ray spectroscopy (EDX) operating at 20 kV, transmission electron microscopy (TEM, JEOL JEM-2010) operating at 200 kV, and photoluminescence (PL) spectroscopy (Perkin Elmer LS 50B) operating at room temperature. 3 Results and discussion XRD patterns of lead molybdate and lead tungstate ( Fig. 1 ) synthesized from different lead salts were indexed to tetragonal phase of PbMoO 4 (JCPDS# 08-0475) and PbWO 4 (JCPDS# 08-0476) [ 13 ]. No PbMoO 4 has been detected in the XRD pattern when lead chloride was used as a starting lead

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Heavily Si-doped InAs photoluminescence measurements

Abstract

In this paper, we present experimental results of photoluminescence for series of InAs:Si heavily doped samples, with doping level varying from 1.6 × 1016 cm-3 to 2.93 × 1018 cm-3. All samples were grown using MBE system equipped with a valved arsenic cracker. The measurements were performed in the temperature range of 20 K to 100 K. Although the Mott transition in InAs appears for electron concentrations above 1014 cm-3, Burstein-Moss broadening of photoluminescence spectra presented in this article was observed only for samples with concentration higher than 2 × 1017 cm-3. For the samples with lower concentrations two peaks were observed, arising from the band gap and defect states. The intensity of the defect peak was found to be decreasing with increasing temperature as well as increasing concentration, up to the point of disappearance when the Burstein-Moss broadening was visible.

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Influence of substrate material on spectral properties and thermal quenching of photoluminescence of silicon vacancy colour centres in diamond thin films

photoluminescence from N-V and Si-V nitrogen-doped ultrananocrystalline diamond film using plasma treatment”, Diamond and Related Materials vo.l. 35, (2013), pp. 36-39. [15] S. Singh and S. A. Catledge, “Silicon vacancy color center photoluminescence enhancement nanodiamond particles by isolated substitutional nitrogen on 100 “ surfaces”, Journal of Applied Physics 113 no. 4 (2013)”, 44701. [16] J. Song, H. Li, F. Lin, L. Wang, H. Wu and Y. Yang, “Plasmon-enhanced photoluminescence of Si-V centers diamond from a nanoassembled metal-diamond hybrid structure

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Determination of temperature dependent parameters of zero-phonon line in photo-luminescence spectrum of silicon-vacancy centre in CVD diamond thin films

Lebedev Physics Institute, vol. 38, No. 10, 2011, pp. 291-296. [14] I. Sakaguchi, M. Nishitani-Gamo, K. P. Loh, H. Haneda, S. Hishita and T. Ando,” Silicon incorporation into chemical vapor deposition diamond: A role of oxygen”, Applied Physics Letters, vol. 71, No. 5, 1997, pp. 629. [15] S. Singh and S. A. Catledge,” Silicon vacancy color center photoluminescence enhancement in nanodiamond particles by isolated substitutional nitrogen on 100 surfaces”, Journal of Ap- plied Physics, vol. 113, No. 4, 2013, pp. 44701. [16] Š

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Investigation on photoluminescence quenching of CdSe/ZnS quantum dots by organic charge transporting materials

Abstract

The effect of different organic charge transporting materials on the photoluminescence of CdSe/ZnS core/shell quantum dots has been studied by means of steady-state and time-resolved photoluminescence spectroscopy. With an increase in concentration of the organic charge transporting material in the quantum dots solutions, the photoluminescence intensity of CdSe/ZnS quantum dots was quenched greatly and the fluorescence lifetime was shortened gradually. The quenching efficiency of CdSe/ZnS core/shell quantum dots decreased with increasing the oxidation potential of organic charge transporting materials. Based on the analysis, two pathways in the photoluminescence quenching process have been defined: static quenching and dynamic quenching. The dynamic quenching is correlated with hole transporting from quantum dots to the charge transporting materials.

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Temperature dependence of Bi4Ge3O12 photoluminescence spectra

Abstract

Bi4Ge3O12 single crystals were obtained using Czochralski growth method. Photoluminescence spectra were analyzed versus temperature from 12 to 295 K. Besides the previously observed emission bands at 610 and 820 nm, the new emission band at 475 nm was found by a careful temperature dependence measurement in the present study. The influence of basic and defect structure on the shape and position of the spectra versus temperature was discussed.

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Electrochemical synthesis of nanoplatelets-like CuS0.2Se0.8 thin film for photoluminescence applications

Abstract

Copper sulfide-selenide (CuS0.2Se0.8) thin films were deposited on FTO coated glass substrate (fluorine doped tin oxide) and stainless steel substrates using electrodeposition technique. Deposited thin films were characterized using different characterization techniques viz. X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis spectroscopy, photoluminescence spectroscopy and surface wettability. XRD study showed polycrystalline nature with cubic phase of the films. Scanning electron microscopy showed that the surface area of the substrate was covered by the nanoplatelets structure of a thickness of 140 to 150 nm and optical study showed that the direct band gap was ~1.90 eV. Surface wettability showed hydrophobic nature of the CuS0.2Se0.8 thin films.

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Photoluminescence properties of ZrO2:Gd3 +, ZrO2:Gd3 + – Dy3+ and ZrO2:Gd3 + – Yb3+ phosphors by Pechini method

Abstract

Zr0.99Gd0.01O2, Zr0.98Gd0.01Dy0.01O2 and Zr0.98Gd0.01Yb0.1O2 phosphors were synthesized by Pechini method at 1200 °C for 12 h in air. The phosphors were characterized by using X-ray powder diffraction (XRD), differential thermal analysis/thermal gravimetry (DTA/TG), scanning electron microscopy (SEM) and photoluminescence spectrofluorometer (PL). X-ray powder diffraction studies showed that the phosphors were crystallized as monoclinic and tetragonal multiphases. The particle size of the phosphors after heat treatment at 1200 °C was found to be of 200 nm to 250 nm. Luminescence studies on these phosphors have been carried out on the emission and excitation, along with lifetime measurements. The results of emission analysis indicate that the phosphors are expected to find potential applications as new optical materials.

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Influence of Bi3+ content on photoluminescence of InNbO4:Eu3+,Bi3+ for white light-emitting diodes

Abstract

A series of red-emitting phosphors InNbO4:Eu3+,Bi3+ was prepared by a high temperature solid-state reaction. The structure, size distribution and luminescence properties of the phosphors were respectively characterized by X-ray diffraction (XRD), laser particle size and molecular fluorescence spectrometer. The XRD results indicate that the phase-pure samples have been obtained and the crystal structure of the host has not changed under the Eu3+ and Bi3+ co-doping. The test of size distribution shows that the phosphor has a normal size distribution. The excitation spectra illustrate that the dominant sharp peaks are located at 394 nm (7F05L6) and 466 nm (7F05D2). Meanwhile, the emission spectra reveal that the phosphors excited by the wavelength of 394 nm or 466 nm have an intense red-emission line at 612 nm owing to the 5D07F2 transition of Eu3+. Bi3+ doping has not changed the peak positions except the photoluminescence intensity. The emission intensity is related to Bi3+ concentration, and it is up to the maximum when the Bi3+-doping concentration is 4 mol%. Due to good photoluminescence properties of the phosphor, the InNbO4:0.04Eu3+,0.04Bi3+ may be used as a red component for white light-emitting diodes.

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