Effect of Ce2O3 on the 1.53 μm spectroscopic properties in Er3+-doped tellurite glasses

Er3+/Ce3+co-doped tellurite-based glasses with composition of TeO 2-Zn O-Na2O are prepared by high-temperature melt-quenching technique.Effects of Ce2O3 content on the 1.53μm band fluorescence spectra and fluorescence lifetime of Er3+are measured and investigated.It is found that the tellurite glass containing Ce2O3 with molar concentration of 0.25%exhibits an increment of 13%in 1.53μm fluorescence intensity and an increment of 15%in the 4I13/2 level lifetime.The results indicate that the prepared tellurite-based glass with a suitable Er3+/Ce3+codoping concentration is an excellent gain medium applied for broadband Er3+-doped fiber amplifier(EDFA)pumped with a980 nm laser diode.     

Ca3Y2(Si3O9)2:Tb3+绿色荧光粉的光谱特性

采用高温固相法制备了Ca₃Y₂(Si₃O₉)₂: Tb³⁺绿色荧光粉,研究了材料的光学性能。X 射线衍射(XRD)结果显示,掺杂少量的Tb³⁺,并未影响Ca₃Y₂(Si₃O₉)₂材料 的晶相结构。Ca₃Y₂(Si₃O₉)₂:Tb³⁺ 荧光粉的激发光谱由较强的4f^75d1宽带吸收(200～300 nm )和较弱的4f-4f电子跃迁吸收 (300～500 nm)构成,主激发峰位于236nm。取波长分别为236、376和482nm的光 作为激发源时,发现样品的主发射峰均位于544 nm,对应Tb³⁺的⁵D 4→⁷F₅跃迁发射。以236nm 紫外光作为激发源,监测544nm主发射峰,随Tb³⁺浓度 的增大,Ca₃Y₂(Si ₃O₉)₂:Tb³⁺的荧光寿命逐渐减小,但在实验范围内并未出现浓度猝灭现象。     

Luminescent property and energy transfer from Ce3+ to Tb3+ in YAl3(BO3)4

A series of Ce³⁺, Tb³⁺ or Ce³⁺/Tb³⁺ doped YAl₃(BO₃)₄ phosphors are synthesized by a high temperature solid-state reaction, and their luminescent properties are investigated. YAl₃(BO₃)₄:Ce³⁺ shows a broad emission band at 422 nm under the 367 nm radiation excitation. YAl₃(BO₃)₄:Tb³⁺ can be efficiently excited by the ultraviolet (UV) light, and produces green emission. The emission intensity of YAl₃(BO₃)₄:Tb³⁺ can be enhanced by adjusting Tb³⁺ doped content, and reaches the maximum at 0.06 mol Tb³⁺. When Ce³⁺ is codoped, the emission intensity of Tb³⁺ in YAl₃(BO₃)₄ can be enhanced, but the commission international del’eclairage (CIE) chromaticity coordinates of YAl₃(BO₃)₄:Tb³⁺ have almost no change. Moreover, the energy transfer from Ce³⁺ to Tb³⁺ in YAl₃(BO₃)₄ is studied.     

Luminescent properties of blue emitting phosphor SrZn2(PO4)2:Eu2+ for white LEDs

Blue emitting phosphor SrZn2(PO4)2:Eu2+ is synthesized by a high temperature solid state method, and the luminescent properties are investigated. At the 330 nm radiation excitation, SrZn2(PO4)2:Eu2+ presents an emission band at 416 nm, which is assigned to the 4f65d1→4f7 transition of Eu2+ ion. The concentration quenching effect of Eu2+ in SrZn2(PO4)2 has been validated and proved to be a resonant type via a dipole-dipole interaction. The critical distance (Rc) of Eu2+ in SrZn2(PO4)2 is calculated to be 3.244 nm. The Commission International de I’Eclairage (CIE) chromaticity coordinates of SrZn2(PO4)2:Eu2+ locate at the blue region, such as (0.150, 0.072). The results indicate that the SrZn2(PO4)2:Eu2+ phosphor may have potential applications in white light emitting diodes (LEDs).     

白光L E D s用新型红色荧光粉的研究进展

简要介绍了光转换型白光L E D s用红色荧光粉的发展现状, 并展望了该方向的发展前景     

入射光调制对Ce∶KNSBN晶体两波耦合的影响

研究了入射光调制条件下Ce∶KNSBN晶体两波耦合动态过程.结果表明,入射光调制抑制了光扇噪音对Ce∶KNSBN晶体两波耦合动态过程的影响,提高了透射信号光强度.同时研究了入射光光强比Ip/Is及入射光总光强Io对最佳调制频率及增益改善Gm/Gf的影响.结果显示,同一Io下,Ip/Is为100时,Gm/Gf到达峰值1.52,对应的最佳调制频率为150 Hz;同一Ip/Is下,Io为57 mW/cm2时,Gm/Gf最大为1.53,对应的最佳调制频率为175 Hz.     

Improved luminescent properties of SrZn2(PO4)2:Sm3+ doped with Li+, Na+ and K+ ions

SrZn2(PO4)2:Sm3+ phosphor was synthesized by a high temperature solid-state reaction in atmosphere. SrZn2(PO4)2:Sm3+ phosphor is efficiently excited by ultraviolet (UV) and blue light, and the emission peaks are assigned to the transitions of 4G5/2-6H5/2 (563 nm), 4G5/2-6H7/2 (597 nm and 605 nm) and 4G5/2-6H9/2 (644 nm and 653 nm). The emission intensities of SrZn2(PO4)2:Sm3+ are influenced by Sm3+ concentration, and the concentration quenching effect of SrZn2(PO4)2:Sm3+ is also observed. When doping A+ (A=Li, Na and K) ions, the emission intensity of SrZn2(PO4)2:Sm3+ can be obviously enhanced. The Commission Internationale de l'Eclairage (CIE) color coordinates of SrZn2(PO4)2:Sm3+ locate in the orange-red region. The results indicate that the phosphor has a potential application in white light emitting diodes (LEDs).     

Improving the luminescence properties of Ba3Eu(PO4)3 by doping Sm3+ as sensitizer

For enhancing the emission intensity and broadening the excitation region of Ba3Eu(PO4)3 (BEP), Sm3+ is doped as sensitizer in this paper. BEP:Sm3+ can produce an obvious red emission at near ultraviolet (n-UV) radiation. An effective energy transfer from Sm3+ to Eu3+ is proved. The commission international de I’Eclairage (CIE) chromaticity coordinates of BEP:Sm3+ locate at red region. When the environment temperature is 150 °C, the emission intensity of BEP:0.10Sm3+ is decreased to 76% of the initial one at room temperature, and the activation energy is calculated to be 0.164 eV, which can prove the good thermal stability of BEP:Sm3+. The results indicate that BEP:Sm3+ may have potential applications in white light emitting diodes (LEDs).     

Dy~(3+)激活的LiSrBO_3材料光谱特性研究

研究了Dy~(3+)激活的LiSrBO_3材料的光谱特性。材料的发射光谱为一多峰宽谱,主峰分别为486,578和668 nm;监测578 nm发射峰时所得材料的激发光谱为一多峰宽谱,主峰分别为331,368,397,433,462和478 nm。研究了Dy~(3+)掺杂浓度对材料发射光谱的影响,结果显示,随Dy~(3+)浓度的增大,黄、蓝发射峰强度比(Y/B)逐渐增大;同时材料的发光强度随Dy~(3+)浓度的增大呈现先增大后减小的趋势,在Dy~(3+)浓度为3 mol%时到达峰值,其浓度猝灭机理为电偶极·偶极相互作用。引入Li~+,Na~+和K~+均可提高材料的发射强度。     

Luminescence properties of tunable red-green emitting phosphor Ba2Ca(BO3)2:Eu3+, Tb3+

A series of Eu3+ or Tb3+ doped Ba2Ca(BO3)2 phosphors were synthesized by a high temperature solid state method, and the luminescence properties are investigated. Ba2Ca(BO3)2:Tb3+ can show an obvious green emission, and the peak locates at 551 nm, which corresponds to the 5D4→7F5 transition of Tb3+. Ba2Ca(BO3)2:Eu3+ can present the characteristic emission of Eu3+, and the peak locates at 600 nm, which is ascribed to the 5D0→7F2 transition of Eu3+. In order to achieve the emission-tunable phosphors, the Eu3+/Tb3+ co-doped Ba2Ca(BO3)2 are synthesized. When tuning the Eu3+ or Tb3+ concentration, Ba2Ca(BO3)2:Eu3+, Tb3+ can both show the tunable emission, which may be induced by the energy transfer from Tb3+ to Eu3+.