Author Affiliations
Abstract
1 State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
2 Key Laboratory of Functional Crystal Materials and Device (Shandong University), Ministry of Education, Jinan 250100, China
For the first time, a group-VI single element nanomaterial was used as the optical saturable absorber (SA) to generate laser pulses. With two-dimensional (2D) tellurene as a passive Q-switch, 1.06 μm and 1.3 μm pulse laser operations were realized from a diode-pumped Nd:YAG crystal. The shortest pulse widths were 98 ns and 178 ns, and the highest peak powers were 2.68 W and 2.45 W, respectively. Our research determines that tellurene is an excellent SA material in the near-infrared region.
tellurene nanosheets absorber graphene passive Q-switching Chinese Optics Letters
2020, 18(4): 041403
1 山东大学 晶体材料国家重点实验室, 山东 济南 250100
2 中国工程物理研究院激光聚变研究中心, 四川 绵阳 621900
3 山东大学 功能晶体材料及器件教育部重点实验室, 山东 济南 250100
搭建了可以连续控制基频光、倍频光偏振夹角的实验平台, 并实现了一系列锗硅玻璃样品的全光极化。极化效果和极化方向由内建电场的大小和方向所决定, 研究了两者与极化光束偏振态以及强度之间的关系。所获得的实验结果基本与经典模型及其推论相一致, 但同时也发现了两者在定量方面的差异, 包括局部变化趋势、角度大小等, 这进一步说明了全光极化过程的复杂性。实验发现, 当基频光与倍频光平行偏振时, 极化过程效果最优; 同时, 极化过程对极化光束的强度也非常敏感。
非线性光学 全光极化 锗硅玻璃 二次谐波产生 nonlinear optics all-optical poling germanosilicate glass second harmonic generation 红外与激光工程
2019, 48(8): 0817002
Author Affiliations
Abstract
1 State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
2 Key Laboratory of Functional Crystal Materials and Device (Shandong University), Ministry of Education, Jinan 250100, China
With tin diselenide (SnSe2) film as a saturable absorber (SA), the passively Q-switched self-frequency doubling (SFD) lasers were realized in Nd3+:ReCa4O(BO3)3 (Re = Y, Gd) crystals. For Nd:YCa4O(BO3)3 crystal, the maximum average output power at 532 nm was 19.6 mW, and the corresponding pulse repetition frequency, pulse duration, single pulse energy, and peak power were 17.6 kHz, 91.9 ns, 1.1 μJ, and 12.1 W, respectively. For Nd:GdCa4O(BO3)3 crystal, these values were 14.5 mW, 22.1 kHz, 48.7 ns, 0.66 μJ, and 13.5 W.
140.3580 Lasers, solid-state 140.3540 Lasers, Q-switched 160.4236 Nanomaterials 160.4330 Nonlinear optical materials Chinese Optics Letters
2019, 17(6): 061402
Author Affiliations
Abstract
1 Key Laboratory of Advanced Laser Materials and Devices, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China
2 State Key Laboratory of Crystal Materials and Institute of Crystal Materials, Shandong University, Jinan 250100, China
3 Key Laboratory of Transparent and Opto-Functional Inorganic Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201800, China
Owing to the small differences between the cross-sections of the four emission peaks around 1.3 μm, an efficient four-wavelength synchronous launched laser is demonstrated using a Nd:GdLuAG crystal. The laser has no special resonator design. The maximum output power is 4.28 W, which corresponds to a conversion efficiency of 45.6%. For the Q-switching, the laser operated in dual-wavelength mode, and the single pulse energy is maintained at ～80 μJ. By calculating the population inversion density, multi-wavelength emission characteristics in both continuous wave and Q-switching lasers are discussed.
140.3380 Laser materials 140.3540 Lasers, Q-switched 300.2530 Fluorescence, laser-induced Chinese Optics Letters
2015, 13(2): 021404
Author Affiliations
Abstract
1 State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
2 Key Laboratory of Functional Crystal Materials and Device, Shandong University, Ministry of Education, Jinan 250100, China
3 Chengdu Fine Optical Engineering Research Center, Chengdu 610041, China
Refractive indices for crystals ammonium dihydrogen phosphate (ADP), 30% deuterated ADP (DADP), 50% DADP, and 70% DADP are measured from 253 to 1529 nm with 5×10 6 accuracy. Numerical fits to modified double-pole Sellmeier equation are made. Second-harmonic generation, third-harmonic generation phase matching (PM) angles, and noncritical PM (NCPM) wavelengths are calculated using the Sellmeier parameters. The deuterated crystals show smaller PM angles than pure crystal. Fourth-harmonic generation process can be realized by DADP in smaller deuterium content than deuterated potassium dihydrogen phosphate (DKDP). The measured NCPM wavelengths are consistent with the calculated value. PM characteristics are compared between DADP and DKDP.
160.4760 Optical properties 160.4330 Nonlinear optical materials 260.1180 Crystal optics 190.4400 Nonlinear optics, materials Chinese Optics Letters
2015, 13(4): 041601
山东大学 晶体材料国家重点实验室，山东 济南 250100
以四方晶系SrWO4晶体为例，研究其非主轴偏振配置的受激拉曼散射特性。用532 nm皮秒脉冲激光作为泵浦源，以单次通过的方式研究了a切SrWO4晶体的受激拉曼散射增益随泵浦光偏振方向的变化，由此确定出拉曼增益的各向异性。针对由 ［WO4］2- 四面体对称伸缩引起的924 cm-1的最强频移的实验显示: 当入射光沿a轴和c轴偏振时，拉曼增益系数出现两个极大值，增益分别为10.1 cm/GW和14.2 cm/GW; 当入射光沿a，c轴中分线方向偏振时，拉曼增益系数出现两个极小值，为7.1 cm/GW。结合拉曼张量及非极性晶格振动模拉曼散射强度解释了上述物理现象，证明了实验结果与理论相符。
钨酸锶晶体 受激拉曼散射 增益系数 各向异性 SrWO4 crystal stimulated Raman scattering gain coefficient anisotropy
1 山东大学 晶体材料国家重点实验室, 济南 250100
2 成都精密光学工程研究中心, 成都 610041
用点籽晶快速生长法在不同温度区间生长了四块氘含量60% DKDP晶体,观察了不同温度下晶体生长过程,同时测量了晶体的透过光谱、摇摆曲线和1053 nm激光损伤阈值。结果表明,在高温区间晶体生长外形优于低温生长的晶体。不同温区晶体的透过光谱并无明显变化,但是随着生长温度的降低,晶体的结构完整性变差,1053 nm激光损伤阈值降低。
DKDP晶体 温度 摇摆曲线 激光损伤阈值 DKDP crystal temperature rocking curve laser induced damage threshold 强激光与粒子束
2014, 26(1): 012006
山东大学 晶体材料国家重点实验室, 山东 济南 250100
加工了不同切向的Nd∶LiGd(MoO4)2晶体, 测量并分析了它们的连续和主动调制激光特性。实验采用激光二极管(LD)端面泵浦的两镜直腔, 其输出镜的耦合透过率为2%。在连续运转条件下, a切和c切晶体的最大输出功率分别为733, 550 mW, 对应的光光转换效率分别为11.3%和6.7%。在声光调Q脉冲运转条件下, a切和c切晶体的最大平均输出功率分别为180, 135 mW, 对应的光光转换效率分别为2.8%和1.7%。当重复频率为10 kHz时, 获得了最佳的脉冲实验结果, 即: 最大单脉冲能量和最高峰值功率来自a切晶体, 分别为15.8 J和85 W; 最小的脉冲宽度来自c切晶体, 为153 ns。实验结果还显示, 不同切向的Nd∶LiGd(MoO4)2晶体具有不同的输出波长, a切晶体为1 061 nm, c切晶体为1 068 nm, 这种多波长发射特性有助于该类晶体在THz波领域的应用。
激光晶体 Nd∶LiGd(MoO4)2晶体 主动调Q 脉冲激光 LD泵浦 laser crystal Nd∶LiGd(MoO4)2 crystal actively Q-switched pulse laser LD pumping
西安电子科技大学综合业务网理论及关键技术国家重点实验室, 陕西 西安 710071
研究了波带交换中的静态业务疏导算法。波带交换可以有效地减少波长交换的端口数量，但是当波带粒度值取固定值时，波带的粒度难以取得合适值。波带的粒度大，有助于减少交换端口的数量，但是波带利用率低；波带粒度小，有助于提高波带利用率，但是交换端口的数量多。为此，提出了多粒度的波带取值方法。根据静态业务疏导与组播路由的相似性，提出了利用构造组播树解决静态疏导问题的方法。另外，为了减少波带与波长交换平面互联的端口数量，采用了同目的地的波带疏导策略，并针对这一疏导策略提出了一种新的波带疏导辅助图。仿真结果表明，相对于固定粒度的波带取值，可以有效地减少交换端口的数量，并提高波带利用率。
光计算 多粒度光交换 波带 组播树 波带业务疏导辅助图
山东大学 晶体材料国家重点实验室， 济南 250100
生长了不同氘含量的磷酸二氘钾(DKDP)晶体，切割角度统一沿Ⅰ类非临界相位匹配方向，即与晶体z轴成90°与x轴成45°，分别在1 064 nm和1 053 nm两种基频波长下进行了四倍频实验，通过测定氘含量与相位匹配角的联系，确定出能够实现非临界四倍频的DKDP晶体的最佳氘含量。实验发现在1 064 nm的基频波长下通过调节DKDP晶体的氘含量无法实现室温的非临界相位匹配，而在1 053 nm基频波长下实现室温的非临界相位匹配的DKDP晶体最佳氘含量为85%左右。
磷酸二氘钾 四倍频 非临界相位匹配 氘含量 deuterated dihydrogen phosphate crystal fourth harmonic generation non-critical phase matching deuterium content
