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1.  Tm^3+-doped Ga2O3-GeO2-Bi2O3-PbO(PbF2) Glasses for 1.47-μm Optical Amplifications  
   石冬梅 张勤远 杨钢锋 刘粤惠 姜中宏《中国物理快报》,2006年第23卷第2期
   We report the spectroscopic properties and thermal stability of Tm^3+-doped Ga2O3-GeO2-Bi2O3-PbO(PbF2) glasses for 1.47-μm optical amplifications. Effects of PbF2 doping on the optical properties and thermal stability of Tm^3+ -doped gallate-germanium-bismuth-lead glass are inestigated. The measured peak wavelength and full width at half-maximum of the fluorescence are 1465nm and - 120 nm, respectively: Siguificant enhancement of the 1.47-μm emission and the lifetime of a a^3H4 level with increasing PbF2 doping have been observed. The presence of GeO2 provides two potentials of increasing the thermal stability and shortening the ultraviolet cutoff band of host glasses.    

2.  Ultra-broad near-infrared emission of Bi-doped SiO2 Al2O3 GeO2 optical fibers  
   吴金东  陈丹平  吴兴坤  邱建荣《中国光学快报(英文版)》,2011年第7期
   Bi-doped SiO 2 –Al 2 O 3 –GeO 2 fiber preforms are prepared by modified chemical vapor deposition (MCVD) and solution doping process. The characteristic spectra of the preforms and fibers are experimentally investigated, and a distinct difference in emission between the two is observed. Under 808-nm excitation, an ultra-broad near-infrared (NIR) emission with full-width at half-maximum (FWHM) of 495 nm is observed in the Bi-doped fiber. This observation, to our knowledge, is the first in this field. The NIR emission consists of two bands, which may be ascribed to the Bi 0 and Bi + species, respectively. This Bi-doped fiber is promising for broadband optical amplification and widely tunable laser.    

3.  Dielectric and Ferroelectric Properties of La-Doped SrBi2Nb2O9 Ceramics  
   刘国珍 顾豪爽 汪春昌 仇杰 吕惠宾《中国物理快报》,2007年第24卷第8期
   Sr1-xLa2x/3Bi2Nb20O (0 ≤ x ≤0.2) ceramic samples are prepared by the solid-state reaction method. Their structure, dielectric and ferroelectric properties are investigated. The incorporation of La^3+ improves the den- sification and decreases the grain size of the ceramics without changing the crystal structure. The remanent polarization 2PT increases with increasing La content and reaches a maximum value of 22.8μC/cm^2 at x = 0.125, which is approximately 60% larger than that of pure SrBi2Nb2O9. The Curie temperature keeps almost unchanged at a value of about 440℃. The relationship between doping and the ferroeleetrie and dielectric properties are discussed.    

4.  Composition Dependence of Spectroscopic Properties of Er^3+ Doped TeO2-WO3-ZnO Glasses  
   李家成 李顺光 胡和方 干福熹《中国物理快报》,2004年第21卷第1期
   Er^3 -doped TeO2-WO3-ZnO glasses were prepared and the absorption spectra, emission spectra and fluorescence lifetimes were measured. With more Te02 content in the glasses, the emission full width at half maximum (FWHM) increases while the lifetime of the ^4I13/2 level of Er^3 decreases. The stimulated emission cross-sectionof Er^3 calculated by the McCumber theory is as large as 0.86pm^2. The product of the FWHM and the emissioncross-section σe of Er^3 in TeO2-WO3-ZnO glass is larger than those in other glasses, which indicates that the glasses are promising candidates for Er^3 -doped broadband amplifiers. The Judd-Otfelt parameter Ω6 shows close composition dependence of the 1.5μm emission bandwidth. The more the TeO2 content is, the larger thevalues of Ω6 and FWHM.    

5.  Spectroscopic properties of Er~(3+)-doped AlF_3-La_2O_3-Al_2O_3-SiO_2 glasses  
   张德宝  陈宝玉  柳祝平  李顺光  胡丽丽《中国光学快报(英文版)》,2004年第4期
   Er~(3+)-doped fluoride lanthanum aluminosilicate glasses with compositions of (65-x/2)SiO_2·(25-x/2)Al_2O_3·xAlF_3·9.1La_2O_3·0.6Er_2O_3·0.3Yb_2O_3(x=4, 8, 12, 20, 30) (mol%) were prepared and their glass transition temperatures and spectroscopic properties were investigated.The Ω_2, Ω_4, and Ω_6 intensity parameters of glasses were calculated by Judd-Ofelt theory from absorption curves. It was found that glasses transition temperature and melting temperature decreased with the increase of fluoride content in glass,Ω_2 decreased gradually with the increase of AlF_3 content,but both Ω_4 and Ω_6 did not increase until AlF_3 content increased to 30 mol%.The quantum efficiency of ~4I_(13/2) to ~4I_(15/2) transition of Er~(3+) ions increases with the increase of AlF_3 content in glass.Fluorescent lifetime is longer in glass containing more AlF_3 content.    

6.  Spectroscopic properties of thulium ions in bismuth silicate glass  
   王欣  胡丽丽  李科峰  田颖  凡思军《中国光学快报(英文版)》,2012年第10期
   A new type of bismuth silicate glass (Bi2O3-SiO2-ZnO-Al2O3-La2O3) doped with Tm2O3 is prepared by melt-quenching method. The thermal stability of the glass is examined by differential scanning calorimetry. No crystallization peak is found. Using the absorption and emission spectra, the absorption and emission cross-sections are calculated. Their maximum data are 2.9×10-21cm2 at 1663 nm and 4.7×10-21cm2 at 1826 nm, respectively. Using the Judd-Ofelt theory, the radiation transition probabilities and radiative lifetimes are obtained. The extended overlap integral method is applied to analyze energy transfer process among the Tm3+ ions. The transfer constants of cross-relaxation and energy migration among the Tm3+ ions at the 3H4 level are 7.60×10-40 and 14.98×10-40 cm6 /s, respectively. The critical transfer radius for cross-relaxation is 0.99 nm. The cross relaxation process is easy to realize and is favorable for obtaining ~2-μm laser.    

7.  Improving luminescent property of SrIn2 O4 :Eu3+ by co-doped A+ (A = Li, Na, K) or Sm3+  
   王志军  李盼来  杨志平  郭庆林《中国物理 B》,2013年第4期
   A series of SrIn2 O4 :Eu3+ phosphors are synthesized by a high temperature solid-state method, and their luminescent properties are investigated. They can be excited by 395-nm radiation, and produce red emission (619 nm); however, they have a low absorption of near-ultraviolet light with the wavelength of 400nm-405 nm. When co-doped with A+ (A=Li, Na, K), the emission intensity of SrIn2O4 :Eu3+ is significantly enhanced, but its emission and excitation spectral profile is unchanged. With co-doping Sm3+ , not only is the emission intensity of SrIn2 O4 :Eu3+ enhanced, but also the absorption is broadened and strengthened in the range of 400 nm-405nm. The effect of Sm3+ -doped content on the emission intensity of SrIn2O4 :Eu3+ , Sm3+ is investigated, and the optimal Sm3+ content is 0.02 mol.    

8.  Magnetic properties and magnetocaloric effects of Mn5Ge3-xGax  
   刘喜斌 张绍英 沈保根 刘喜斌 张绍英 沈保根《中国物理 B》,2004年第13卷第3期
   We report on the magnetic properties and magnetocaloric effects of Mn5Ge3-xGax compounds with x=0.1,0.2,0.3,0.4,0.6 and 0.9. All samples crystallize in the hexagonal Mn5Si3-type structure with space group P63/mcm and order ferromagnetically.The Curie temperature of these compounds decreases with increasing x, from 306K (x=0.1) to 274K (x=0.9).The average Mn magnetic moments increases with increasing Ga content,reaching a maximum value at x=0.6.The magnetic entropy changes in these compounds are determined from the temperature and field dependence of the magnetization using the thermodynamic Maxwell relation.The Ga substitution has two kinds of influence on the magnetocaloric effect (MCE) of Mn5Ge3.One is that the magnitude of the magnetic entropy change decreases,the other is that the MCE peak becomes broadened.    

9.  Superconductivity and Transport Properties in Th and F Codoped Sm1-xThxFeAsO1-yFy  
   李玉科  林效  陶前  陈航  王操  李林军  罗永康  何咪  朱增伟  曹光旱  许祝安《中国物理快报》,2009年第1期
   A series of Th and F co-doped superconductors Sm1-xThxFeAsO1-yFy are synthesized and the variation of superconductivity with the doping level is investigated. At the fixed Th doping level x = 0.1, the superconducting transition temperature Tc increases monotonically with F content, and finally Tc reaches a maximum of about 55K around y = 0.1, and saturates for even more F content the normal state thermopower increases monotonically with 'overdoped' regime is not observed and possible explanation (y = 0.15). Similar to the SmFeAsO1-y Fy system, the doping level. However the decrease of Tc in the is discussed.    

10.  Near-infrared downconversion in Eu2+ and Pr3+ co-doped KSrPO4 phosphor  
   孙家跃  孙翊宁  朱吉成  曾军辉  杜海燕《中国物理 B》,2013年第5期
   A novel near-infrared (NIR) downconversion (DC) phosphor KSrPO4 :Eu2+ , Pr3+ is synthesized by the conventional high temperature solid-state reaction. The Eu2+ acts as an efficient sensitizer for Pr3+ in the KSrPO4 host. With broad-band near-ultraviolet light excitation induced by the 4f→5d transition of Eu2+ , the characteristic NIR emission of Pr3+ , peaking at 974 nm and 1019 nm due to 3P0 → 1G4 and 1G4 → 3H4 transitions, is generated as a result of the energy transfer from Eu2+ to Pr3+ . The luminescence spectra in both the visible and the NIR regions and the decay lifetime curves of Eu2+ prove the energy transfer from Eu2+ to Pr3+ . This Eu2+ and Pr3+ co-doped KSrPO4 phosphor may be a promising candidate to modify the spectral mismatch behavior of crystalline solar cells and sunlight.    

11.  Elevation of the Power Factor of Co4Sb12 Skutterudite with Sm-Doping in High-Pressure High-Temperature Synthesis  
   JIANG Yi-Ping  JIA Xiao-Peng  GUO Wei  XU Hui-Wen  DENG Le  ZHENG Shi-Zhao  MA Hong-An《中国物理快报》,2010年第27卷第6期
   A thermoelectric material Smx Co4Sb12 (0( x ≤1.0) is synthesized at high pressure and high temperature leading to an enhanced power factor. The experimental measurements show that the SmxCo4Sb12 compounds exhibits n-type conduction. The absolute value of the Seebeck coefficient decreases with increasing Sm fraction. The resistivity increases with samarium content x from 0.1 to 0.2, but decreases dramatically when x changes from 0.2 to 1.0. The maximum power factor reaches 13.1 μW.cm^-1K-2 at x =1.0, which is larger than the data previously reported for the La-doped CoSb3 prepared at room pressure.    

12.  Spectroscopic properties in Er3+/yb3+ Co-doped fluorophosphate glass  
   郑涛  秦杰明  蒋大勇  吕景文  肖生春《中国物理 B》,2012年第4期
   Using the technique of high-temperature melting, a new Er3+/Yb3+ co-doped fluorophosphate glass was prepared. The absorption and fluorescence spectra were investigated in depth. The effect of Er3+ and Yb3+ concentration on the spectroscopic properties of the glass sample was also discussed. According to the Judd Ofelt theory, the oscillator strength was computed. The lifetime of 4113/2 level (t-m) of Er3+ ions was 8.23 ms, and the full width at half maximum of the dominating emission peak was 68 nm at 1.53 μm. The large stimulated emission cross section of the Er3+ was calculated by the McCumher theory. The spectroscopic properties of Er3+ ion were compared with those in different glasses. The full width at half maximum and σe are larger than those of other glass hosts, indicating this studied glass may be a potentially useful candidate for high-gain erbium-doped fiber amplifier.    

13.  Thermoelectric properties of lower concentration K-doped Ca_3Co_4O_9 ceramics  
   李亚男  吴平  张师平  陈森  闫丹  杨金光  王立  淮秀兰《中国物理 B》,2018年第5期
   The tuning of electron and phonon by ion doping is an effective method of improving the performances of thermoelectric materials. A series of lower concentration K-doped Ca_(3-x)K_xCo_4O_9(x = 0, 0.05, 0.10, 0.15) polycrystalline ceramic samples are prepared by combining citrate acid sol-gel method with cold-pressing sintering method. The single-phase compositions and plate-like grain morphologies of all samples are confirmed by x-ray diffraction and field emission scanning electron microscope. The effects of lower concentration K doping on the thermoelectric properties of the material are evaluated systematically at high temperatures(300–1026 K). Low concentration K doping causes electrical conductivity to increase up to 23% with little effect on the Seebeck coefficient. Simultaneously, the thermal conductivity of K-doped sample is lower than that of the undoped sample, and the total thermal conductivity reaches a minimum value of approximately1.30 W·m~(-1)·K~(-1), which may be suppressed mainly by the phonon thermal conduction confinement. The dimensionless figure-of-merit ZT of Ca_(2.95)K_(0.05)Co_4O_9 is close to 0.22 at 1026 K, representing an improvement of about 36% compared with that of Ca_3Co_4O_9, suggesting that lower concentration K-doped Ca_3Co_4O_9 series materials are promising thermoelectric oxides for high-temperature applications.    

14.  Optimum fluorescence emission around 1.8 μm for LiYF4 single crystals of various Tm3+-doping concentrations  
   李珊珊  夏海平  符立  董艳明  谷雪梅  章践立  王冬杰  张约品  江浩川  陈宝玖《中国物理 B》,2014年第10期
   In this paper, optical spectra of LiYF4 single crystals doped with Tm3+ ions of various concentrations are reported. The emission intensity at 1.8 ktm first increases with increasing Tm3+ concentration, and reaches a maximum value when the concentration of Tm3+ is about 1.28 mol%, then it decreases rapidly as the concentration of Tm3+ further increases to 3.49 mol%. The emission lifetime at 1.8 p.m also shows a similar tendency to the emission intensity. The maximum lifetime of 1.8 μm is measured to be 17.68 ms for the sample doped with Tm3+ of 1.28 mol%. The emission cross section of 3F4 level is calculated. The maximum reaches 3.76 × 10 -21 cm2 at 1909 nm. The cross relaxation (3H6, 3H4 →3 F4, 3F4) between Tm3+ ions and the concentration quenching effect are mainly attributed to the change of emission with Tm3+ concentration. The largest quantum efficiency between Tm3+ ions is estimated to be ,-147% from the measured lifetime and calculated radiative lifetime. All the results suggest that the Tm3+/LiYF4 single crystal may have potential applications in 2 μm mid-infrared lasers.    

15.  Host dependent thermal stability and frequency upconversion of Er^3+-doped heavy metal oxyfluoride germanate glasses  
   徐时清  方达伟  张在宣  赵士龙  张丽艳  王宝玲  姜中宏《中国物理》,2005年第14卷第11期
   The upconversion properties of Er^3+-doped heavy metal oxyfluoride germanate glasses under 975 nm excitation have been investigated. The intense green (551 and 529 nm) and relatively weak red (657 nm) emissions corresponding to the transitions ^4S3/2→^4I15/2, ^2H11/2→^4 I15/2 and ^4F9/2 →^4I15/2, respectively, were simultaneously observed at room temperature. The content of PbF2 has an important influence on the upconversion luminescence emission. With increasing content of PbF2, the intensities of green (529 nm) and red (657 nm) emissions increase slightly, while the green emission (551 nm) increases markedly. These results suggest that PbF2 has an influence on the green (551 nm) emission more than on the green (529 nm) and red (657 nm) emissions.    

16.  Optical temperature sensor based on up-conversion fluorescence emission in Yb3+:Er3+ co-doped ceramics glass  
   徐伟  李成仁  曹保胜  董斌《中国物理 B》,2010年第19卷第12期
   Yb3+:Er3+co-doped oxy-fluoride ceramics glass has been prepared.The mechanism of up-conversion emissions about Er3+was discussed,and the temperature properties of green up-conversion fluorescence between 303 and 823 K were investigated.The results show that the sensitivity of this sample reaches its maximum value,about 0.0047 K 1,when the temperature is 383 K,indicating that this kind of sample can be used as high temperature and high sensitivity optical temperature sensor.    

17.  Temperature Dependence of the Fluorescence Emission Intensity of Eu/TiO2 Nanocrystals  
   曾庆光 丁泽军 巨新 王忆 盛业青《中国物理快报》,2007年第24卷第5期
   The samples of europium ions doped titanium dioxide (Eu^3+/TiO2) nanocrystals are synthesized by a modified sol-gel method with hydrothermal treatment. The x-ray diffraction and scanning electron microscopy are used to characterize the sample. The temperature-dependent fluorescence emission effect of Eu^3+-doped samples is investigated. It is found that under the excitation of 514.5nm light, the emission intensity of Eu^3+ reaches a maximum value at 450K among various Eu^3+ dopant concentrations in Eu^3+ /TiO2 nanocrystals. The variation of the emission intensity may be attributed to the photon-assist absorption and the temperature-quenching effect.    

18.  Multiferroic properties of sol-gel derived Bi5Fe1-xCoxTi3O15 thin films  
   王伟  武鑫华  毛翔宇  陈小兵《中国物理 B》,2011年第7期
   Co-doped Bi 5 FeTi 3 O 15 thin films (BFCT-x,Bi 5 Fe 1-x Co x Ti 3 O 15) were prepared using a sol-gel technique.XRD patterns confirm their single phase Aurivillius structure,and the corresponding powder Rietveld analysis indicates the change of space group around x=0.12.The magnetic hysteresis loops are obtained and ferromagnetism is therefore confirmed in BFCT-x thin films.The remanent magnetization (M r) first increases and reaches the maximum value of 0.42 emu/cm 3 at x=0.12 due to the possible Fe 3+-O-Co 3+ ferromagnetic coupling.When x=0.25,the M r increases again because of the dominant Fe 3+-O-Co 3+ ferromagnetic coupling.The remanent polarization (2P r) of BFCT-0.25 was measured to be as high as 62 μC/cm 2,a 75% increase when compared with the non-doped BFCT-0 films.The 2P r remains almost unchanged after being subjected to 5.2 × 10 9 read/write cycles.Greatly enhanced ferroelectric properties are considered to be associated with decreased leakage current density.    

19.  Investigation of the mechanism of upconversion luminescence in Er3+/Yb3+ co-doped Bi2Ti2O7 inverse opal  
   严冬  杨正文  廖佳燕  吴航俊  邱建备  宋志国  周大成  杨勇  尹兆益《中国光学快报(英文版)》,2013年第4期
   Bismuth (Bi)-doped materials have attracted a great deal of attention because of their broadband nearinfrared (near-IR) emission around the wavelength utilized in telecommunications. In this study, broad near-IR emission band from 1 100 to 1 650 nm is generated in the Bi-doped 90GeS2-10Ga2S3 glass and glass-ceramics under 820 nm of light excitation. Based on the analysis of the absorption and emission spectra, the origin of this broadband emission is ascribed to the Bi2-2 dimers. The precipitation of β-GeS2 nanocrystals drastically enhances the emission intensity and lifetime of Bi-doped chalcogenide glass.    

20.  Synthesis,Crystal Structure and Photophysical Property of 2-(9H-carbazol-9-yl)-3-(2-(2,4,5-tri-(9H-carbazol-9-yl)-3,6-dicyanophenoxy)phenoxy) dibenzo[b,e][1,4]dioxine-1,4-dicarbonitrile  
   董亚芳  余荣民  卢灿忠《结构化学》,2018年第9期
   A purely organic compound 2-(9 H-carbazol-9-yl)-3-(2-(2,4,5-tri-(9 H-carbazol-9-yl)-3,6-dicyanophenoxy)phenoxy)dibenzo[b,e][1,4]dioxine-1,4-dicarbonitrile, C_(76) H_(40) N_8 O_4, was synthesized and characterized by NMR, UV-Vis, photoluminescenceand X-ray single-crystal structure analysis. The compound crystallizes in monoclinic system, space group P2_1/n with a = 11.6537(3), b = 34.9738(8), c = 15.5053(3) ?, β =101.992(2)°, V = 6181.6(2)?~3, Z = 4, M_r= 1129.18 g/mol, D_c =1.396 g/cm~3, F(000) =2672, μ = 2.239 mm~(–1), GOOF = 1.019, the final R = 0.0577 and wR= 0.1559 for 11925 observed reflections with I 2σ(I). The UV-vis absorption and fluorescence of the compound were discussed. The compound exhibitsyellow-green luminescence with maximum emission peak at 538 nm, and quantum yields of ф = 0.25 and 0.48 in air-equilibrated and degassed toluene at room temperature. Transient decay spectral studies show that compound 1 displays two component decay fashions with a short decay lifetime of 23 ns for the prompt fluoresce anda long decay lifetime of 3.8ms for thermally activated delayed fluorescence. In air-equilibrated toluene, only a short decay lifetime of 17 ns was observed.The experimental and computational results show thatthe emission of the compound originates from the CT excited states.    

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