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飞秒光谱技术的现状与展望 总被引:3,自引:0,他引:3
自1981年R.L.Fork等人利用环型腔可饱和吸收体的对撞锁模技术首次产生了飞秒(10-15s)激光脉冲后,多频段飞秒光脉冲的产生、放大、频率扩展及光脉冲压缩等技术的发展十分迅速.目前在物理学、生物学和化学等各领域中,利用飞秒光谱技术观测各种原初过程以及超快速现象,巳经成为一种崭新而有效的研究手段,越来越受到各国科学家的高度重视.本文介绍了飞秒光源的现状、飞秒光谱的主要测量方法以及飞秒光脉冲放大、压缩等技术的基本原理,并对飞秒光谱技术的未来发展及应用前景进行了讨论. 相似文献
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飞秒激光与超快现象(Ⅰ) 总被引:2,自引:0,他引:2
文章第Ⅰ部分介绍飞秒激光的发展过程和应用概况,讨论了飞秒脉冲产生和测量的基本原理,以及近年来在物理和技术上的新进展.特别介绍了在飞秒激光器全固体化、小型化、高效化方面的进步.有关飞秒激光技术在超快现象研究中的应用将在第Ⅱ部分介绍. 相似文献
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文章第I部分介绍飞秒激光的发展过程和应用概况,讨论了飞秒脉冲产生和测量的基本原理,以及近年来在物理和技术上的新进展,特别介绍了在飞秒激光器全固体化,小型化,高效化方面的进步,有关飞秒激光技术在超快现象研究中应用将在第Ⅱ部分介绍。 相似文献
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随着飞秒(1fs=1×10-15s)激光技术的不断成熟,飞秒激光器不但在实验室能产生小于10fs的光脉冲,啁啾放大后的飞秒光脉冲的聚焦峰值功率密度可达到1021W/cm2以上,而且飞秒激光系统已实现全固体、小型化结构,其稳定性和可靠性大大提高,因此在科学技术研究中的应用越来越广.文章重点介绍飞秒激光的主要特性和它与透明介质[如熔融石英、光学玻璃、对激光透明的高分子聚合物(PMMA)等]的相互作用过程,分析它们之间的非线性相互作用过程引起的材料特性或结构变化的物理机制和可能的应用,尤其在高密度大容量三维存储和微光子器件制造等方面的应用可能性. 相似文献
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文章主要介绍了1999 年诺贝尔化学奖得主艾哈默德·泽维尔(Ahmed.H.Zewail) 教授的获奖工作———用飞秒技术和飞秒光谱的方法研究化学反应飞秒相干动力学,叙述了它们的原理、方法和应用,并简要介绍了其获奖背景、重要意义、相关研究及应用展望. 相似文献
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回顾了短暂时间间隔测量的历史。条纹概念的引入、电光源和电子仪器的使用、激光的出现使能测量到的短暂时间间隔大大缩短。由于对撞脉冲锁模和啁啾脉冲压缩新概念的提出,人们将脉冲宽度压缩到了几个飞秒。介绍了自锁模钛宝石激光器的锁模、放大和调谐的工作原理以及飞秒技术在物理学、生物学、化学控制反应、光通讯等领域中的应用。 相似文献
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飞秒激光剥蚀电感耦合等离子体质谱在地球科学中的应用进展 总被引:4,自引:0,他引:4
激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)是原位微区元素含量和同位素比值分析测试的主流技术, 已被广泛应用于地球科学等相关领域。飞秒激光剥蚀系统由于其极短的激光脉宽大大降低甚至消除了传统纳秒激光剥蚀产生的热效应导致的元素分馏问题,在非基体匹配分析等方面显示出巨大发展潜力,已成为当前LA-ICP-MS技术的一个新的发展趋势和研究热点。介绍了飞秒激光剥蚀系统的基本特征(飞秒激光及产生原理、当前商用飞秒激光器种类),重点阐述了飞秒激光剥蚀地球科学样品的机理(样品对激光能量的吸收方式、气溶胶的产生和粒度分布特征、剥蚀坑的形貌特征等),评述了飞秒激光剥蚀在改善分析性能方面的独特优势,最后总结了近十几年来它在地球科学样品元素含量和同位素比值分析中的实际应用,并展望了该技术的应用前景。 相似文献
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In recent years, femtochemistry and femtobiology have been quickly progressing. The specific characteristics of femtosecond pulses have extended the possibilities of traditional experiments and allowed obtaining new previously inacceptable information. New lines of research have emerged. This publication overviews studies performed at the Semenov Institute of Chemical Physics of the Russian Academy of Sciences. These studies cover three new directions: the mechanisms of intramolecular physicochemical processes occurring on the femto-picosecond timescale, coherent photochemistry based on the action of femtosecond pulses, and physicochemical processes initiated by multiphoton absorption of femtosecond radiation. The scope of these directions is illustrated by the results of studies of actual chemical and biological systems. 相似文献
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中红外波段覆盖重要的分子吸收区与多个大气透射窗口,该波段的超快激光器在多个领域具有广泛应用。基于光纤的中红外超快激光器近年来在激光发射与传输、超快脉冲产生与应用等方面发展迅速,为中红外波段超快激光开辟了新的研究手段与应用领域。综述了近十年来中红外超快光纤激光器的发展概况,介绍了近年来中红外波段的激光传输与增益手段。其中,重点回顾了近年来中红外超快脉冲产生技术的研究进展及其代表性工作,包括非线性偏振旋转、可饱和吸收体以及频移反馈锁模技术。此外,还介绍了中红外超快脉冲的压缩放大技术与超连续谱产生应用。最后讨论并总结了中红外超快光纤激光器面临的挑战与可能的发展方向。 相似文献
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《Comptes Rendus de l''Academie des Sciences Series IV Physics》2001,2(10):1483-1504
Ultrafast magneto-optical techniques, using femtosecond laser pulses, are a powerful tool for investigating the magnetization dynamics in metallic materials. We review some recent developments in this field, which allow progress in the understanding of the fundamental mechanisms that govern the magnetization changes in ferromagnetic structures. Some fundamental aspects of the magneto-optical response in the frequency and time domain are first considered. Then, we analyze the dynamics of the charges and spins following the optical excitation of quasiparticles in different ferromagnetic thin films. This dynamics is discussed by considering the processes that are involved in the ultrafast magneto-optical response. 相似文献
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This review summarizes the recent progress in the study of ultrafast nonthermal effects of light on magnetic materials. It is demonstrated that due to opto‐magnetic phenomena an intense 100 fs circularly polarized laser pulse acts on the spins similar to an equivalently short effective magnetic field pulse up to 1 T. The review shows that using such opto‐magnetic phenomena one may selectively excite different modes of magnetic resonance, realize quantum control of magnons, trigger magnetic phase transitions and switch spins on a subpicosecond time‐scale. All these findings open new insights into the understanding of ultrafast magnetic excitation and, considering recent progress in the development of compact ultrafast lasers, may provide new prospects for applications of ultrafast opto‐magnetic phenomena in magnetic storage and information processing technology. 相似文献
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Two-dimensional materials-decorated microfiber devices for pulse generation and shaping in fiber lasers 下载免费PDF全文
Two-dimensional(2D) materials have been regarded as a promising nonlinear optical medium for fabricating versatile optical and optoelectronic devices. Among the various photonic applications, the employment of 2D materials as nonlinear optical devices such as saturable absorbers for ultrashort pulse generation and shaping in ultrafast lasers is one of the most striking aspects in recent years. In this paper, we review the recent progress of 2D materials based pulse generation and soliton shaping in ultrafast fiber lasers, and particularly in the context of 2D materials-decorated microfiber photonic devices. The fabrication of 2D materials-decorated microfiber photonic devices, high performance mode-locked pulse generation, and the nonlinear soliton dynamics based on pulse shaping method are discussed. Finally, the challenges and the perspective of the 2D materials-based photonic devices as well as their applications are also discussed. 相似文献
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Xue-Wen Chen Ahmad Mohammadi Amir Hossein Baradaran Ghasemi 《Molecular physics》2013,111(20):3003-3012
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Lagrange T Reed BW Santala MK McKeown JT Kulovits A Wiezorek JM Nikolova L Rosei F Siwick BJ Campbell GH 《Micron (Oxford, England : 1993)》2012,43(11):1108-1120
The growing field of ultrafast materials science, aimed at exploring short-lived transient processes in materials on the microsecond to femtosecond timescales, has spawned the development of time-resolved, in situ techniques in electron microscopy capable of capturing these events. This article gives a brief overview of two principal approaches that have emerged in the past decade: the stroboscopic ultrafast electron microscope and the nanosecond-time-resolved single-shot instrument. The high time resolution is garnered through the use of advanced pulsed laser systems and a pump-probe experimental platforms using laser-driven photoemission processes to generate time-correlated electron probe pulses synchronized with laser-driven events in the specimen. Each technique has its advantages and limitations and thus is complementary in terms of the materials systems and processes that they can investigate. The stroboscopic approach can achieve atomic resolution and sub-picosecond time resolution for capturing transient events, though it is limited to highly repeatable (>10(6) cycles) materials processes, e.g., optically driven electronic phase transitions that must reset to the material's ground state within the repetition rate of the femtosecond laser. The single-shot approach can explore irreversible events in materials, but the spatial resolution is limited by electron source brightness and electron-electron interactions at nanosecond temporal resolutions and higher. The first part of the article will explain basic operating principles of the stroboscopic approach and briefly review recent applications of this technique. As the authors have pursued the development of the single-shot approach, the latter part of the review discusses its instrumentation design in detail and presents examples of materials science studies and the near-term instrumentation developments of this technique. 相似文献
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《Physics Reports》1999,321(6):253-305
Infrared spectroscopy on ultrafast time scales represents a powerful technique to investigate the nonequilibrium dynamics of elementary excitations in bulk and nanostructured semiconductors. In this article, recent progress in this field is reviewed. After a brief introduction into electronic excitations below the fundamental bandgap and ultrafast processes in semiconductors, infrared pulse generation and the methodology of time-resolved infrared spectroscopy are reviewed. The main part of this paper is devoted to coherent optical polarizations and nonequilibrium excitations of the electronic system in the spectral range below the fundamental band gap. The focus is on the physics of single component plasmas, i.e. electrons or holes. In particular, intraband, inter-valence and intersubband transitions are considered. Processes of phase relaxation, carrier and energy redistribution are analyzed. The potential of ultrafast infrared technology and spectroscopy for future applications is discussed in the final part. 相似文献
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Yb3+离子掺杂YAG晶体(Yb∶YAG)作为一种性能优良的激光晶体已广泛应用于高效、高功率激光领域。最新研究表明,Yb∶YAG晶体响应时间可达0.411 ns,其优良的超快闪烁特性在超快脉冲辐射探测、惯性约束核聚变、空间辐射探测、核反应动力学等领域的应用引起了广泛关注,使得Yb∶YAG晶体成为超快闪烁材料研究的热点。关于Yb∶YAG的闪烁特性,文章在系统介绍Yb∶YAG作为超快闪烁晶体研究进展和发光机理的基础上,归纳总结了掺杂种类、浓度、后处理工艺、辐照、格位尺寸大小、温度等对Yb∶YAG晶体闪烁性能的影响。然后,针对Yb∶YAG目前存在的问题,给出相应的解释并提出通过离子共掺调控来改善其闪烁性能的方法。最后,对Yb∶YAG超快闪烁晶体未来的发展方向进行了展望。 相似文献