Laser pulsetrain pulse-picker for subharmonic frequencies

我们请求支持为现有的研究购买配件-激光系统，其物理研究通常由NSERC发现拨款资助，光子学研究通过资助CIPI的特殊应用提供资金，以及安大略省卓越中心的生物物理学研究。这笔拨款将加强三名教授和五名研究生的工作。*现有的激光系统是完整和有效的；*这台设备将允许我们在进行超快激光-材料相互作用时获得新的机制，用于光学、材料加工或与先进和发展中的激光外科相关的生物问题相互作用。*我们最近在这一领域拥有一项专利，但进展有限，我们已经让位于哈佛大学的Mazur这样的团队。设备：开发一个脉冲拾取器选择系统，在两个不同的激光器之间高效共享，使我们能够配置我们的100 MHz激光脉冲串，以提供50 MHz、25 MHz、12 MHz或各种脉冲组合，以传输到不同的材料或生物组织。科学界：与随后的晶格热化相比，飞秒激光将激光能量沉积到电子中的时间刻度较短。1 MHz)在晶格能量完全耗散之前将下一个能量脉冲沉积到电子，材料热松弛。根据控制这两个时间尺度范围内的通量传输的范例，我们相信我们可以对玻璃和其他光学材料的状态进行非平衡操纵，并在纳米尺度上做到这一点。本质上，我们想要在任何时候控制材料中电子和声子之间的能量分配-大约，以分别影响材料中的化学碰撞和热/机械碰撞。我们已经展示了这给我们提供了进入新材料科学的途径以及微加工不同玻璃、陶瓷和其他脆性材料的新方法。

We request support to buy accessories for an existing research-laser system, for which physics research is generally funded by NSERC Discovery grant and photonics research by funding for special applications from CIPI, as well as biophysics research by Ontario Centres of Excellence.  Three professors and five graduate students work will be enhanced by this grant.   The existing laser-system is complete and functional;  this equipment will permit us to access new regimes in the way in which laser pulses are delivered when doing ultrafast laser-materials interaction for optics, materials-processing, or biotissue interaction relevant to advanced and developmental laser surgery.  We have a recent patent in this area, but progress has been resource-limited, and we have given up some ground to groups like that of Mazur at Harvard.   The Equipment:  a pulse-picker selection system, to be efficiently shared between two different lasers, that will let us configure our 100MHz laser pulsetrain to deliver instead 50 MHz, 25 MHz, 12 MHz, or various combinations of pulses for delivery to different materials or biotissues.   The Science:  Femtosecond lasers are known to deposit laser energy into electrons on a timescale short compared to the subsequent thermalization to the lattice.  High repetition-rate lasers (> 1 MHz) deposit the next pulse of energy to electrons before this lattice-energy has fully dissipated, and the material relaxed thermally.  By the paradigm of controlling fluence delivery across these two time-scale regimes, we believe we can make non-equilibrium manipulations of the state of glasses and other optical materials, and do this at a nanometer-scale.  Essentially, we want to control, at any time, the partition of energy between electrons and phonons in the material - approximately, to influence the chemical impact and the thermal/mechanical impact in the material separately.  We've shown this gives us access to new materials science, and new ways of microprocessing different glasses, ceramics and other brittle materials.