Novel diagnostics for the characterization of ultrashort laser pulses

2019年，超快激光市场的价值为42.1亿美元，预计到2025年将达到160亿美元。由于超快激光的市场正在迅速增长，对其特征的诊断将变得同样重要。其中，能够恢复其脉冲持续时间的光谱仪和设备是必不可少的。这可以通过激光脉冲的时间分布由它们的光谱和光谱相位来定义的事实来容易地理解。为了优化和获得最短的脉冲宽度，拥有测量光谱和光谱相位的装置是绝对必要的。虽然在可见光和近红外光谱范围内存在许多用于诊断超短激光脉冲的技术，并且可以在商业上使用，但在IR和中红外范围内的技术并不广泛。近年来，INRS研究人员与学术界和产业界合作，开发了两种诊断红外和中红外超短脉冲的技术。第一种技术是基于多光子吸收的光谱仪，与现有技术相比，它具有为红外激光器的光谱表征提供低成本设备的潜力，具有更高的灵敏度和光谱分辨率。这将与少周期公司密切研究。第二种技术，Frost，能够表征从可见光到中红外的脉冲，并且没有相位匹配。因此，Frost是描述能够产生单周期持续时间的倍频程激光脉冲的理想方法。对于单周期脉冲，定义其时间结构的另一个重要参数是其载波包络相位(CEP)。INRS的研究人员已经开发了第三种技术来表征CEP的激光快照波动。对于第二和第三项技术，在双方合作伙伴的支持下，INRS的研究人员将通过研究单周期脉冲的产生和特征以及在高重复频率下跟踪CEP来将它们推向极限。在这个项目结束时，我们的技术将达到更高的TRL(从3到6)，从而使它们能够转移到包括我们的工业合作伙伴在内的加拿大公司。

The market for ultrafast lasers was representing a value of 4.21B US$ in 2019 and is expected to reach 16B$ by 2025. Since the market for ultrafast lasers is rapidly growing, diagnostics for their characterization will become equally important. Among them, spectrometers and devices capable to retrieve their pulse duration are absolutely essential. This can be easily understood by the fact that the temporal profile of laser pulses is defined by their spectra and spectral phase. To optimize and to get the shortest pulse duration, it is absolutely essential to have devices to measure the spectra and the spectral phase. While in the visible and near infrared spectral range many technologies for the diagnostics of ultrashort laser pulses exist and are available commercially, technologies are not widely available for the IR and mid-IR range. Over the recent years, INRS researchers with academic and industrial collaborators have developed two technologies for the diagnostics of IR and mid-IR ultrashort pulses. The first technology is a spectrometer based on multiphoton absorption and bears the potential to provide low cost devices for spectral characterization of IR lasers with improved sensitivity and spectral resolution compared to current technologies. This will be investigated closely with few-cycle Inc. The second technology, FROSt, is capable to characterize pulses from the visible to the mid-IR and is free of phase matching. Therefore, FROSt is ideal to characterize octave spanning laser pulses capable to produce single-cycle duration. For single-cycle pulses, another important parameter to define their temporal structure is their carrier envelope phase (CEP). INRS researchers have developed a third technology to characterize laser shot-to-shot fluctuations of the CEP. For the second and third technology, INRS researchers with support of both partners will push them to their limit by investigating the generation and characterization of single-cycle pulses and the tracking of CEP at high repetition rate. At the end of this project, our technologies will reach a much higher TRL (from 3 to 6) thus enabling their transfers to Canadian companies including our industrial partners.