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1.
刘一先  李富铭 《中国激光》1987,14(3):141-143
本文报道了用锁模磷酸盐玻璃激光的倍频光泵浦若丹明B超短腔染料激光器的实验装置和实验结果,用TPF和OSA的组合装置研究了磷酸盐玻璃激光器的最佳运转条件,得到了脉宽~5ps的锁模脉冲系列,以此ps光源泵浦的染料激光器获得了波长为620.1~641.6nm,脉冲宽度小于4ps的单模可调谐激光输出。  相似文献   

2.
周广勇  任燕  王春  王东  邵宗书  蒋民华 《中国激光》2001,28(10):901-904
报道了一种新型上转换染料———反式 4 [4’ (N 羟乙基 N 乙基胺基 )苯乙烯基 ] N 甲基吡啶 对甲苯磺酸盐(trans 4 [4’ (N hydroxyethyl N ethylamino)styryl] N methylpyridiniump toluenesulfonate ,简称HEASPS)DMF溶液的激光上转换性质和光限幅性质。用Z 扫描技术测得其双光子吸收截面为σ2 =4.7× 10 -4 8cm4 ·s/photon ,研究了它在DMF溶剂中的线性吸收、单光子荧光、双光子荧光和双光子激射特性 ,用再吸收效应解释了双光子荧光峰相对单光子荧光峰的红移现象 ,该染料的激射和再吸收现象相互竞争导致了双光子激射峰相对于双光子荧光峰的蓝移现象。在 10 6 4nm皮秒脉冲激光的激发下 ,可得强烈的 6 2 6nm上转换激射光 ,上转换效率最高为 15 .5 % ,从抽运光到激射光的净转换效率为 2 6 %。该染料的DMF溶液表现出明显的光限幅特性  相似文献   

3.
利用偏硼酸钡(BBO)倍频晶体,实现了1064 nm激光泵浦金刚石拉曼激光器的高重复频率紫外激光脉冲输出。搭建了腔内倍频金刚石拉曼激光器,实现了620 nm激光输出。当1064 nm泵浦光的功率为4.0 W时,620 nm输出激光的功率为550 mW,转换效率约为13.7%。通过BBO晶体腔外倍频,获得了平均功率约为48 mW的310 nm紫外激光脉冲输出,脉冲重复频率为2 kHz,脉冲宽度约为761.8 ps,倍频效率约为8.7%。  相似文献   

4.
10 GHz再生锁模光纤激光器获得光纤超连续谱的研究   总被引:2,自引:1,他引:1  
报道了利用10GHz再生锁模光纤环形激光器(RML-FRL)获得波长在1528~1563nm连续可调、脉宽为4.6~5.8ps的短脉冲输出作为高稳定的光纤超连续(SC)谱泵浦源。对RML-FRL输出的脉冲直接放大泵浦4.5km色散位移光纤(DSF),得到20dB带宽46.08nm的SC谱输出,经阵列波导光栅(AWG)谱切片后,得到间隔100GHz、中心波长符合ITUT标准的30信道输出,脉宽在6.5~7.8ps,示波器显示任意信道的抖动均值小于1.4ps。  相似文献   

5.
用氩离子激光(514nm)泵浦掺Nd玻璃光纤产生激光;并观察到超荧光辐射现象。激光阈值为2.4mW,转换斜率21%。激光输出功率与泵光功率呈线性关系。超荧光现象则没有明显的阈值,输出与泵光呈非线性关系。  相似文献   

6.
基于无波分裂脉冲产生的平坦超连续谱被报道。笔者采用非线性偏振旋转(NPR)作为锁模方法来实现耗散孤子脉冲和无波分裂脉冲的切换输出。在0.3 W的泵浦功率下,获得了耗散孤子脉冲。脉冲宽度为5.8 ps,脉冲间隔为54 ns,与11.05 m的腔长一致,信噪比为55 dB,压缩后的脉冲宽度为0.61 ps。值功率可以被提升到1.18 kW。通过适当调整腔偏振态和增加泵浦功率,耗散孤子可以演化为无波分裂脉冲。随着泵浦功率的提高,脉冲宽度从11.7 ps增加到20.2 ps,几乎增加了两倍。经过计算,时间带宽积从23.9增加到53.43。较大的啁啾可以抵抗非线性相移的影响,从而避免脉冲分裂。无波分裂脉冲的脉冲能量可以提高到3.89 nJ,是耗散孤子脉冲能量的五倍。随后,使用耗散孤子和无波分裂脉冲作为种子源去获得超连续谱。结果表明,在锥形高非线性光纤中,无波分裂脉冲产生的超连续谱范围和平坦度均优于耗散孤子脉冲。基于耗散孤子脉冲和无波分裂脉冲产生的超连续谱范围为1 400~2 000 nm,覆盖了S波段、C波段、L波段三个主要通信波段,20 dB带宽分别为310.3 nm和426.4 nm。这项工...  相似文献   

7.
用重复率脉冲锁模YAG激光同步泵浦四种激光染料,获得脉冲重复率20Hz、峰值功率MW级、平均功率mW级、脉宽30ps染料激光。波长复盖范围为550.0~689.0nm,谱线宽度0.05nm。实验比较了L_D=1/2L_PF和L_D=L_P两种匹配腔的输出特性。  相似文献   

8.
用主被动锁模Nd:YAG倍频脉冲序列同步泵浦若丹明染料激光器,在染料激光腔端插入吸收体二乙基噁二碳化青碘化物(DODCI),腔内压缩激光脉冲。在λ=598nm附近,对不同宽度泵浦脉冲均观察到很好的压缩趋势。条纹相机测得的光脉冲明显变得光滑对称。探讨了压缩机理。  相似文献   

9.
为突破传统光纤激光器因增益介质为稀土掺杂光纤,辐射波长相对固定的困境,由于量子点尺寸依赖的辐射波长,本文提出全正常色散锁模PbSe量子点光纤激光器,通过数值计算得到了1.7μm稳定的耗散孤子锁模,并系统地数值研究了使用该激光器输出耗散孤子的启动动力学、谐振腔内激光的演化和激光器的稳态输出特性,探索了增益光纤的长度和浓度、谐振腔的长度对输出特性的影响。当泵浦功率为0.1 W时,最佳的增益光纤长度为0.3 m,掺杂浓度为12×1021 m-3,此时的脉冲宽度为7.59 ps,光谱的宽度为13.77 nm,耗散孤子在单模光纤长度为2~7 m范围内保持稳定。当被动光纤长度为0.1 m时,激光器输出了22个峰、包络宽度为22.33 nm的多波长激光,光谱覆盖了1678~1724 nm,此时时域中观察到一对间隔为4 ps、单脉冲宽度为0.92 ps的孤子对。该研究结果对超快量子点光纤激光器的建立和优化提供了理论指导,为特殊波长超快光纤激光提供了新的选择。  相似文献   

10.
本文目的是设计一个能够实现高稳定性、窄脉宽、高峰值功率的全固态532nm脉冲激光输出系统.首先采用平-平腔结构,运用LD侧面泵浦技术和电光调Q技术实现基频光输出,再用KTP晶体通过腔外倍频实现脉冲绿光激光输出.在腔长为164cm,重复频率200Hz,泵浦电流为70A,泵浦脉宽为230μs条件下,得到单脉冲能量1.68m...  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

15.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

16.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

17.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

18.
A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.  相似文献   

19.
Call for Papers     
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks  相似文献   

20.
正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first  相似文献   

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