DESIGN OF HIGH REPETITION RATE FEMTOSECOND LASERS

高重复率飞秒激光器的设计

• 批准号: 6480809
• 负责人: ROBIN Main HOCHSTRASSER
• 金额: $ 15.58万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6480809
• 关键词: biological products; biomedical resource; lasers

A self mode-locked titanium sapphire laser has been constructed following the design of Murnane, Kapteyn, Huang, Asaki and Garvey from Washington State University. This laser produces the shortest pulses available directly from a laser oscillator. It is based in a very simple design which comprises two end mirrors, one of which is an output coupler, two fold mirrors which focus the beam into the Tisapphire crystal and a pair of prisms which compensate the temporal dispersion associated with the crystal. The laser is pumped with approximately 5W of multi-line output from a continuous wave argon ion laser. Short pulses are achieved by minimizing the third order phase dispersion in the laser cavity. This involves the use of a small, 4.75 mm crystal, single stack cavity mirrors which are chosen to give the flattest spectral response over about 150 nm and a pair of fused silica prisms instead of the more commonly used dispersive glasses. Typical pulse widths from the laser are between 11 and 13 fs at a repetition rate of 85 MHz with a power of about 5 nJ. The noise is only that arising from the argon pump laser, typically less than 1%. The high repetition frequency and reasonable high peak power is allowing some measurements to be done directly using lock-in detection. However, for most applications the laser needs to be further amplified. This was achieved in a new design of regenerative amplifier. A high energy pulse around 1 mJ can be produced at a 1 kHz frequency having a width between 30 and 50 fs. The generation of a white light continuum from this source allows pump probe experiments to be performed throughout the visible region of the spectrum. Frequency doubling and difference frequency generation yield high powered near UV and infra-red pulses with sub 100 fs pulse widths. Highly stable laser systems are under study.

已经建造了一个自锁的钛蓝宝石激光器 遵循Murnane，Kapteyn，Huang，Asaki和Garvey的设计 华盛顿州立大学。 该激光产生最短的脉冲 直接可从激光振荡器获得。 它基于一个 简单的设计包括两个端镜，其中之一是 输出耦合器，两个折叠镜，将光束聚焦到 tisapphire晶体和一对棱镜，以补偿时间 与晶体相关的分散体。 激光泵送 来自连续波氩离子的多线输出约为5W 激光。 通过最小化三阶阶段来实现短脉冲 激光腔中的分散体。 这涉及使用小的 4.75毫米晶体，单堆腔镜，被选为给出 大约150 nm和一对融合的最平坦的光谱响应 二氧化硅棱镜代替了更常用的色散玻璃。 激光器的典型脉冲宽度在A处的11至13 fs。 重复率为85 MHz，功率约为5 NJ。 噪音是 仅是由氩气泵激光产生的，通常小于1％。 高重复频率和合理的高峰值功率是 允许使用锁定直接进行一些测量 检测。 但是，对于大多数应用，激光需要 进一步放大。 这是在新的再生设计中实现的 放大器。 可以在1 kHz下产生大约1 MJ的高能量脉冲 宽度在30至50 fs之间。 一代 该来源的白光连续体允许泵探测实验 在整个频谱的可见区域中执行。 频率加倍和差异频率产生很高 在紫外线和红外脉冲附近供电，其脉冲宽度为100 fs。 高度稳定的激光系统正在研究中。