REPAIR OF FEMTOSECOND LASER SYSTEM

这个NSERC-RTI应用程序用于修复我所在团队的飞秒激光系统。我的团队在过去两年中处理了三起重大激光故障：一起发生在2017年年中，一起发生在2017年底，最后一起发生在2019年冬季。第一次和第三次故障与振荡器腔内激光介质的损坏有关，而第二次故障与激光放大器内的激光晶体损坏有关；据说是由前者触发的。对于这些故障中的每一次，我们都能够通过替换损坏的晶体来恢复系统运行，以获得新的斑点，由于我们在激光物理方面的专业知识以及缺乏支付此类维修费用的资金，这些程序是在激光公司的远程协助下进行的。激光振荡器继续退化，过去六个月测量到的功率稳定性缓慢而持续下降就是明证。这台机器必须送到工厂去。修复将包括用一个新开发的具有更高损伤阈值的装置替换激光振荡器，并改变展宽器/压缩器中的放大晶体和栅格，以改善横向光束质量。*由于这项资金申请是为了维修一个为定制仪器提供能量的非常昂贵和专门的飞秒激光装置，因此附近没有其他更具成本效益的替代方案或类似设备。前面提到的激光故障已经多次影响了我的团队的研究效率。由于永久故障将阻碍硕士和博士论文的完成，因此迫切需要修理这台设备。

This NSERC-RTI application is for the repair of my group's femtosecond (fs) laser system. My team has dealt with three major laser failures in the last two years: one in mid 2017, one in late 2017, and the last one in winter 2019. The first and third failures were related to damage of the laser medium in the oscillator cavity while the second one involved damage of the laser crystal within the laser amplifier; supposedly triggered by the former. For each of these failures, we were able to bring the system back to operation by displacing the damaged crystals in order to obtain fresh spots, procedures that were performed with remote assistance from the laser company owing to our expertise in laser physics and the lack of funds to pay for such a repair. The laser oscillator continues to degrade as evidenced by the slow and constant decrease of power stability measured over the last six months. The unit must be sent to the factory. The repair will involve the replacement of the laser oscillator by a newly developed unit with a higher damage threshold and changing the amplifying crystals and the gratings in the stretcher/compressor to improve the transverse beam quality.******Since this funding request is for the repair of a very costly and specialized fs-laser unit that energizes custom-built instruments, there are no other more cost-effective alternatives or availability of similar equipment in the vicinity. The aforementioned laser failures already affected the research productivity of my team multiple times. There is an immediate need to repair this equipment since a permanent breakdown will impede the completion of MSc and PhD theses.