透射式SESAM实现掺Yb^3＋光纤激光器被动调Q锁模

锁模光纤激光器具有体积小、性能稳定及模式好等优点，日益受到关注。利用一种新型的透过式半导体可饱和吸收镜，实现双包层掺Yb^3＋光纤激光器调Q锁模脉冲激光输出。得到的脉冲调Q包络半高宽约500ns，重复频率110kHz，平均输出功率45mW，锁模脉冲重复频率26．7MHz。锁模光路比反射式吸收镜更简单，易于调节，为进一步引入色散补偿元件进行飞秒脉冲的实验研究奠定了基础。

用表面态型半导体可饱和吸收镜实现Yb∶YAG激光器被动调Q锁模

制作了一种新型的半导体可饱和吸收镜--表面态型半导体可饱和吸收镜.用表面态型半导体可饱和吸收镜作为被动锁模吸收体实现了半导体端面泵浦Yb∶YAG激光器被动调Q锁模.在泵浦功率仅有1.4 W的情况下,获得了调Q锁模脉冲序列,锁模平均输出功率1 mW,锁模脉冲重复频率200 MHz.

Passive Q-switching of diode-pumped Yb:YAG microchip laser with ion-implanted GaAs

We reported a passive Q-switched diode laser pumped Yb:YAG microchip laser with an ion-implanted semi-insulating GaAs wafer. The wafer was implanted with 400-keV As^(+) in the concentration of 10^(16) ions/cm^(2). To decrease the non-saturable loss, we annealed the ion-implanted GaAs at 500 oC for 5 minutes and coated both sides of the ion-implanted GaAs with antireflection (AR) and highreflection (HR) films, respectively. Using GaAs wafer as an absorber and an output coupler, we obtained 52-ns pulse duration of single pulse.

离子注入GaAs实现双包层掺镱光纤激光器被动调Q锁模

用离子注入的半绝缘GaAs晶片作为吸收体和输出镜,在双包层掺镱光纤激光器上实现了调Q锁模.离子注入的能量为400keV的As+离子,注入剂量为1016/cm2,然后在600℃下退火20min.当抽运功率为5W时,脉冲平均输出功率为200mW,调Q包络重复频率为50kHz,半高宽为4μs,锁模脉冲重复频率为15MHz。

长波长半导体可饱和吸收镜的研制及其在固体激光器被动锁模和调Q中的应用

介绍了国际上流行的长波长半导体可饱和吸收镜的研制方法及其在固体激光器被动锁模和被动调Q中所起的作用,并分别就Cr4+:YAG,Cr:Forsterite等激光器进行了阐述.

Passive Q-Switching in a Flash-Lamp Pumped Nd∶YAG Laser with Ion-Implanted GaAs Wafer

A passive Q-switched flash-lamp-pumped Nd:YAG laser with the ion-implanted semi-insulating GaAs water is reported．The wafer is implanted with 400keV As~+ ions in the concentration of 10~(16)cm~(-2). Using GaAs wafer as an absorber and an output coupler．62ns pulse duration of single pulse is obtained.

用半导体可饱和吸收镜对掺钕晶体激光器进行被动调Q和锁模

较全面介绍了几种掺钕激光晶体的光学性质。就掺钕激光晶体主要的三个波长探讨了用一种新型的吸收体（半导体可饱和吸收镜）进行被动调Q和锁模。

量子阱激光二极管泵浦Nd:YLF固体激光器的调Q

于2010-11-23批量导入

Scan test in 18x8 bits Booth Coding-Wallace Tree multiplier

Scan test can be inserted around hard IP cores that have not been designed with DFT approaches. An 18x18 bits Booth Coding-Wallace Tree multiplier has been designed with full custom approach with 0.61 m CMOS technology. When we reuse the multiplier in another chip, scan chain has been inserted around it to increase the fault coverage. After scan insertion, the multiplier needs 4.7% more areas and 24.4% more delay time, while the fault coverage reaches to 95%.

Measurement of the isospin-filtering dd → 4He K+K- reaction at Q = 39 MeV

The total cross-section for the dd → 4HeK+K− reaction has been measured at a beam momentum of 3.7GeV/c, corresponding to an excess energy of 39MeV, which is the maximum possible atthe Cooler Synchrotron COSY-Jülich. A deuterium cluster-jet target and the ANKE forward magnetic spectrometer, placed inside the storage ring, have been employed in this investigation. We find a total cross-section of σtot < 14 pb, which brings into question the viability of investigating the dd → 4He a0(980)reaction as a means of studying isospin violation.

低速Ar~(q+)(q=7—14)离子入射Au表面激发的X射线谱

研究了高电荷态离子40Arq+(q=7—14)轰击金属Au表面产生的特征X射线谱。实验结果表明,在弱束流(nA量级)的情况下,对于动能相同的入射离子,当电荷态比较高(q=11)时,便能有效地激发靶原子的特征X射线,单离子的X射线产额高达10-8量级。分析结果显示,入射离子的势能、动能和这种相互作用特有的镜像相互作用势能沉积在靶表面,使靶原子内壳层电子激发和电离,形成空穴和产生外壳层电子填充空穴辐射特征X射线,特征X射线的产额随入射离子的势能(电荷态)的增加而增加。

高电荷态离子Ar~(q+)与Nb作用产生的X射线谱

利用光谱技术在超导离子源SECRAL上研究了10~20keV·q的Arq+(q=16,17)离子入射在金属Nb表面产生的X射线谱.实验结果表明,高电荷态Ar16+离子在金属表面中性化过程中存在着多电子激发,Ar16+的K壳层电子被激发产生空穴,级联退激发射Ar的Kα特征X射线.Ar空心原子的K层发射X射线的强度随入射离子的动能减弱,靶原子Nb的L层发射X射线强度随入射离子动能的增加而增强.Ar17+单离子的Kα-X射线产额比Ar16+单离子的Kα-X射线产额大3个数量级.