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萃英研究生沙龙
“萃英”研究生学术沙龙第二期
发布日期:2005-11-05浏览次数:

9159金沙申请大厅"萃英"研究生学术沙龙第二期

9159金沙申请大厅"萃英"研究生学术沙龙第二期

9159金沙申请大厅“萃英”研究生学术沙龙第二期活动于11月5日上午十点在物理楼中212教室如期举行。光学专业01级直博生安然同学给我们带来了题为“透明材料中的飞秒激光维纳制备”的精彩报告。报告结束之后安然同学和参与的同学进行了深入的交流。

安然同学师从龚旗煌教授和李焱教授,从事“飞秒科学”的研究,已在国际性的学术刊物上发表数篇高质量的学术论文。他深入浅出地介绍了飞秒激光在微制备和微加工领域的研究情况和热点问题,介绍了他们实验小组在飞秒激光烧蚀制备微通道及利用飞秒激光微爆炸制作计算全息图方面的工作,并展望了飞秒激光微纳制备技术在微光学、微光电子学、生物医学以及航天科学等许多领域的应用前景。安然同学的报告生动有趣,在座的同学都被深深地吸引,报告结束后,大家都非常积极地参与了讨论和交流,沙龙的氛围变得更加热烈和融洽。

这次活动是”萃英”学术沙龙的第二期,研究生会吸取了第一次活动的经验,对这次活动的准备工作进行了改进和完善,加上参与沙龙的同学们的热情支持,使得第二期的活动取得了圆满的成功。

“萃英”沙龙取“群英荟萃”之意,旨在加强学术交流,提高研究水平,激励9159金沙申请大厅涌现一批活跃在科研前线的研究生精英。沙龙每两周举办一次,将邀请北大9159金沙申请大厅的优秀研究生代表作为主讲人,主讲话题将涵盖9159金沙申请大厅的所有学科。欢迎同学们继续关注并广泛参与!

安然同学的研究心得:

  1. 多思考:勤于思考是创新的源泉;

  2. 多总结:归纳总结是创新的基础;

  3. 多讨论:交流讨论是创新的火花;

  4. 多实验:设计实验是创新的过程。

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"萃英"研究生学术沙龙第二期资料

主 讲 人:安然(光学01级直博)导 师:龚旗煌教授、李焱教授研究方向:飞秒科学报告题目:透明材料中的飞秒激光微纳制备沙龙时间:11月5日上午10:00沙龙地点:物理大楼中212安然br/>科研简历:安然,9159金沙申请大厅光学专业01级直博生,师从龚旗煌教授、李焱教授,从事飞秒科学研究,已在国际性的学术刊物上发表数篇学术论文。发表论文为:

  • An Ran, Li Yan*, Dou Yanping, Fang Ying, Yang Hong, Gong Qihuang**, “Laser micro-hole drilling of soda-lime glass with femtosecond pulses”, Chin. Phys. Lett., 21(2004) 2465-2468.

  • Ran An, Yan Li*, Yanping Dou, Hong Yang, and Qihuang Gong**, “Simultaneous multi-microhole drilling of soda-lime glass by water-assisted ablation with femtosecond laser pulses”, Opt. Express., 13( 2005)1855-1859.

  • Ran An, Yan Li*, Yanping Dou, Dayong Liu, Hong Yang, and Qihuang Gong**, “Water-assisted drilling of microfluidic chambers inside silica glass with femtosecond laser pulses”, accepted by Appl. Phys. A.

报告摘要:飞秒激光具有极短的脉冲宽度和极高的峰值功率,不仅可以加工硬度或熔点极高的材料,而且可以通过多光子过程在玻璃和聚合物等透明材料中诱导出微结构,并且具有精确的损伤阈值,很小的热影响区域,能够进行亚衍射极限精度的制备和加工。因此近年来飞秒激光在微制备和微加工领域已引起了人们广泛的兴趣。通过使聚焦的飞秒脉冲只在焦点处的能流密度超过材料结构变化阈值,能够在透明材料的任何位置实现超精细三维结构的制备。例如,利用飞秒激光辐照诱导的折射率变化制作波导、光栅、耦合器等;利用材料内部的微爆炸实现三维存储和其它三维点阵结构的制备;通过界面烧蚀进行打孔、切割和刻蚀;利用飞秒光辐照区域更易被化学药剂选择性腐蚀,实现微通道与微流体器件的制备;以及利用双光子聚合制备光子晶体、二元光学元件和微光机电器件等。可以预见,随着飞秒激光技术和材料研究的不断进步与成熟,飞秒激光微纳制备技术必将在微电子、微光学、微光电子学以及生物医学、航天科学等许多领域展现出更加广阔的前景。Femtosecond laser offers ultrashort pulse width, which makes it easy to achieve extreme high peak intensity with low pulse energy. Nonlinear multiphoton absorption takes place during the femtosecond laser–matter interaction due to high enough intensity. Therefore, femtosecond laser processing has the advantages including deterministic material modification and damage thresholds, smaller heat-affected zones and the ability to machine sub-diffraction-limit target regions. This has encouraged increasing interest in the use of femtosecond lasers for precise micro/nano-structuring of a wide range of materials. When femtosecond laser pulses were focused by an objective lens with a high numerical aperture, various three-dimensional structures can be fabricated at arbitrary position of a transparent medium. Femtosecond laser-induced refractive index change is applied to fabricate waveguides, gratings and couplers. Microexplosion inside materials was used for three-dimensional bit-oriented storage and fabrication of other dot-arrayed structures; Drilling, cutting and etching are carried out by interface ablation; Microchannels and microfluidic devices are processed due to femtosecond laser modified regions preferentially etched away by chemical solution. Photonic crystals, binary optical elements and microelectromechanical systems are achieved by femtosecond laser two-photon polymerization. Obviously, with the progress of ultrafast laser technology and material science, femtosecond laser micro/nano-fabrication technique will play a more important role in applications of microelectronics, microphotonics, biomedicine and aerospace.