可用于钕玻璃激光系统的自锁模飞秒激光器

描述了用激光二极管抽运的全固体Ｎｄ：ＬＭＡ自锁模飞秒激光振荡器,通过理论计算和分析,在其腔内加入－非线性系数较大的介质,同时对腔结构进行优化设计,实现了自锁模。它直接产生波长为１０５４ｎｍ的激光,输出激光脉冲的宽度达６１０ｆｓ,光谱宽度为２．１ｎｍ,输出功率达１５ｍＷ。     

Nd:LMA自锁模飞秒激光器腔结构最佳化设计

Nd:LMA晶体相对低的非线性折射率n₂,使得针对Ti:Sapphire自锁模激光器设计的腔,对Nd:LMA介质而言并没有提供足够的自幅度调制(SAM).为了在Nd:LMA激光器上实现自锁模,在腔内引入一个具有大的非线性系数n₂、快的响应时间的SF57介质,这样就使得激光腔的结构比较特殊.在这篇文章里利用ABCD传输矩阵对该激光器的结构从理论上进行了分析和计算,使腔结构达到了最佳化设计.     

大模场啁啾光纤光栅的光谱特性

 将一种矩阵算法拓展应用于数值求解多模耦合模微分方程, 并使用该矩阵算法对大模场啁啾光纤光栅的光谱特性进行了理论研究。结果表明, 大模场多模光纤光栅因模式的自耦合和互耦合而使反射谱存在多个反射峰, 这与单模光纤光栅的反射谱不同。由于光栅周期存在啁啾, 大模场光纤光栅的反射峰分裂, 且峰值反射率减小。使用高斯切趾函数可使反射峰分裂在一定程度上得到改善。     

Applications of polymethacrylate-based monoliths in high-performance liquid chromatography

Monolithic columns were introduced in the early 1990s and have become increasingly popular as efficient stationary phases for most of the important chromatographic separation modes. Monoliths are functionally distinct from porous particle-based media in their reliance on convective mass transport. This makes resolution and capacity independent of flow rate. Monoliths also lack a void volume. This eliminates eddy dispersion and permits high-resolution separations with extremely short flow paths. The analytical value of these features is the subject of recent reviews. Nowadays, among other types of rigid macroporous monoliths, the polymethacrylate-based materials are the largest and most examined class of these sorbents. In this review, the applications of polymethacrylate-based monolithic columns are summarized for the separation, purification and analysis of low and high molecular mass compounds in the different HPLC formats, including micro- and large-scale HPLC modes.     

Diode-Pumped Monolithic Nd:LMA Laser

Ｄｉｏｄｅ－ＰｕｍｐｅｄＭｏｎｏｌｉｔｈｉｃＮｄ：ＬＭＡＬａｓｅｒ￥ＬＵＪｉａｎｇ；ＨＵＡＮＧＺｈａｏｍｉｎｇ；ＪＩＮＺｈｅｎｈｏｎｇ；ＷＡＮＧＹａｎｇｊｕｎ（ＯｐｔｉｃａｌＦｉｂｅｒＩｎｓｔｉｔｕｔｅ，，ＳｈａｎｇｈａｉＵｎｉｖｅｒｓｉｔｙｏｆＳｃ...     

Review of recent advances in the preparation of organic polymer monoliths for liquid chromatography of large molecules

In recent years the use of monolithic polymers in separation science has greatly increased due to the advantages these materials present over particle-based stationary phases, such as their relative ease of preparation and good permeability. For these reasons, these materials present high potential as stationary phases for the separation and purification of large molecules such as proteins, peptides, nucleic acids and cells. An example of this is the wide range of commercial available polymer-based monolithic columns now present in the market.     

激光二极管泵浦Nd：LMA激光器的连续波输出研究

报道有一个３Ｗ激光二极管端面泵浦Ｎｄ：ＬＭＡ激光器，实验采用三镜折迭像散补偿腔。在１０５４ｎｍ波长，激光器连续输出功率达６２０ｍＷ，斜率效率为５０％，光－光转换效率２０％，在１０８３ｎｍ波长处，激光器连续输出功率为６４ｍＷ，斜率效率为６％，光转换效率２．１％。     

Adiabatic bend transitions for large mode area fibres

Adiabatic bend transitions in large mode area multimode fibres were investigated theoretically using the beam propagation method. Adiabatic bend transducers preserve the power of guided light in the fundamental mode while guiding from one level of curvature to another for improved operation of mode filters and fibre amplifiers. A method is shown and used to find the optimised guidance path. Applications of these transducers include modal power back-converters, and guidance paths into and out of higher order mode filtering devices which work on bending.     

Review on recent and advanced applications of monoliths and related porous polymer gels in micro-fluidic devices

This review critically summarises recent novel and advanced achievements in the application of monolithic materials and related porous polymer gels in micro-fluidic devices appearing within the literature over the period of the last 5 years (2005-2010). The range of monolithic materials has developed rapidly over the past decade, with a diverse and highly versatile class of materials now available, with each exhibiting distinct porosities, pore sizes, and a wide variety of surface functionalities. A major advantage of these materials is their ease of preparation in micro-fluidic channels by in situ polymerisation, leading to monolithic materials being increasingly utilised for a larger variety of purposes in micro-fluidic platforms. Applications of porous polymer monoliths, silica-based monoliths and related homogeneous porous polymer gels in the preparation of separation columns, ion-permeable membranes, preconcentrators, extractors, electrospray emitters, micro-valves, electrokinetic pumps, micro-reactors and micro-mixers in micro-fluidic devices are discussed herein. Procedures used in the preparation of monolithic materials in micro-channels, as well as some practical aspects of the micro-fluidic chip fabrication are addressed. Recent analytical/bioanalytical and catalytic applications of the final micro-fluidic devices incorporating monolithic materials are also reviewed.     

Two-loop Majorana neutrino mass and magnetic moment in a gauge model

Two-loop contributions to Majorana mass and transition magnetic moment in a gauge model not in conflict with decaying neutrino dark matter (DDM) hypothesis have been studied. Another variant of an earlier model [J Dhar and S Dev,Pramana — J. Phys. 39 541 (1992)] consistent with the DDM hypothesis is proposed and is shown to lead to large enough neutrino magnetic moment and consistent with the phenomenological constraints on neutrino mass.