共查询到18条相似文献,搜索用时 171 毫秒
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Tm3+掺杂SrAl2O4:Eu2+的光激励和热释光性能 总被引:2,自引:2,他引:0
通过高温固相法制备出Sr0.98-xAl2O4:0.02Eu2+,xTm3+(x=0,0.01,0.02,0.03,0.04,0.05)系列样品,并对其光激励和热释光性能进行了研究。在SrAl2O4:Eu2+原有陷阱能级结构的基础上,通过Tm3+的掺杂引入了更深的陷阱TB,并增加原有陷阱TA浓度,进而优化了材料的光存储容量及光激励特性。对比研究了系列样品的初始光激励发光强度和热释光强度随着Tm3+掺杂量的变化规律,证实陷阱TB为光激励发光提供了有效俘获中心。当Tm3+的掺杂摩尔分数x=0.03时,材料中的陷阱TB的浓度达到最高值,同时光激励发光强度最大。对比Tm3+共掺前后热释光图谱,通过Chen's半宽法计算出了引入陷阱TB的陷阱深度。实验结果证实材料中TB的浓度对其光激励发光性能起着决定性的作用。在980 nm激发下,由深陷阱TB释放出来的电子可以再次被浅陷阱TA俘获,这种浅陷阱TA的再俘获效应在光激励发光过程中表现为光激励余辉现象。 相似文献
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通过理论模拟对具有上覆盖层的SiO2脊形条波导结构进行了优化,在此基础上利用微电子工艺制作了SiO2脊形波导Mach-Zehnder型电光调制器,并进行热极化引起的电光和非线性效应的研究.热极化过程大幅增强了样品的电光及非线性效应,二次电光系数由热极化前的1.56×10-22(m/V)2提高到热极化后的8.50×10-22(m/V)2,极化后得到了0.093pm/V的线性电光系数,对热极化的物理机理进行了理论分析.
关键词:
电光调制器
2光波导')" href="#">SiO2光波导
电光效应
热极化 相似文献
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Reversible photo-induced volume changes have been observed accompanying reversible optical absorption edge shift produced by successive cycles of band gap illumination and annealing for well-annealed evaporated As2S3 and As4Se5Ge1 films. The As2S3 film shows an increase in its volume by illumination, while As4Se5Ge1 film shows a decrease. Qualitative discussion has been given in connection with pressure-induced optical constant change. 相似文献
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During thermal annealing or light irradiation, the changes in the valence states of vapour-deposited As2S3 and As4S4 films were observed by UPS. The experimental results reveal that an as-deposited As2S3 film contains considerable numbers of As4S4 molecular units, which polymerize or cross link to form a As2S3 glassy network on annealing or irradiation. 相似文献
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T. Yamabe K. Tanaka A. Tachibana Y. Kobayashi H. Teramae K. Fukui 《Solid State Communications》1981,40(5):521-523
We have studied the electronic structure of As4S5 molecule as a model of the local pyramidal structure in amorphous As2S3 film. Emphasis has been put on the analysis of the behaviour of a trapped electron in this model concerning the consequent structural relaxation. It has been found that As4S5 species has affinity for an excess electron, and that the attachment of an excess electron promotes the cleavages of specific As-S bonds. 相似文献
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The results of the femtosecond optical heterodyne detection of optical Kerr effect at 805 nm with the 80 fs ultrafast pulses in amorphous Ge10As40S30Se20 film is reported in this paper. The film shows an optical non-linear response of 200 fs under ultrafast 80 fs-pulse excitation, and the values of real and imaginary parts of non-linear susceptibility χ(3) were 9.0×10−12 and −4.0×10−12 esu, respectively. The large third-order non-linearity and ultrafast response are attributed to the ultrafast distortion of the electron orbits surrounding the average positions of the nucleus of Ge, As, S and Se atoms. This Ge10As40S30Se20 chalcogenide glass would be expected as a promising material for optical switching technique. 相似文献
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Studies on electrodeposited As2S3 thin films by double exposure holographic interferometry technique
N.S. Shinde V.B. Prabhune H.D. Dhaigude C.D. Lokhande V.J. Fulari 《Applied Surface Science》2009,255(20):8688-8694
Arsenic trisulphide (As2S3) thin films have been deposited onto stainless steel and fluorine doped tin oxide (FTO) coated glass substrates by electrodeposition technique using arsenic trioxide (As2O3) and sodium thiosulphate (Na2S2O3) as precursors and ethylene diamine tetracetic acid (EDTA) as a complexing agent. Double exposure holographic interferometry (DEHI) technique was used to determine the thickness and stress of As2S3 thin films. It was observed that the thickness of the thin film increases whereas film stress to the substrate decreases with an increase in the deposition time. X-ray diffraction and water contact angle measurements showed polycrystalline and hydrophilic surface respectively. The bandgap energy increases from 1.82 to 2.45 eV with decrease in the film thickness from 2.2148 to 0.9492 μm. 相似文献
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Existence of As3S2 compound which is stable in a certain temperature range higher than room temperature has been confirmed in AsAs2S2 system. Photo-synthesis effect of As3S2 crystal from As and As2S2 mixture, namely light induced conversion from a crystalline state to another crystalline state, has also been investigated. 相似文献
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Infrared reflection and transmission measurements in AsχTe1?χ glasses (45?×?55) show well-defined Gaussian vibrational absorption peaks. Comparisons with spectra observed in crystalline and glassy As2S3 and As2Se3 indicate that the local order in AsχTe1?χ glasses is not like that found in crystalline As2Te3, but rather it consists primarily of AsTe3 pyramids which are probably linked together in a fashion similar to that found in As2S3 and As2Se3. 相似文献
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P.H. Cannington H.J. Whitfield 《Journal of Electron Spectroscopy and Related Phenomena》1977,10(1):35-44
The He(I) UV photoelectron spectra of As4S3, P4S3, P4Se3 and As4O6 are reported in this paper. The spectra of As4S3 and the isostructural molecules P4S3 and P4Se3 comprise seven broad but clearly defined peaks, whilst the spectrum of As4O6 consists of six peaks and two shoulders. By comparing the spectra with one another and with the photoelectron spectra of other arsenic and phosphorus compounds, the character and symmetry species of the highest-energy occupied molecular orbitals of the molecules have been assigned. 相似文献