Novel diagnostics for the characterization of ultrashort laser pulses

2019年，超快激光器的市场价值为42.1亿美元，预计到2025年将达到160亿美元。由于超快激光器的市场正在迅速增长，对其特性的诊断将变得同样重要。其中，能够检索脉冲持续时间的光谱仪和设备是绝对必要的。激光脉冲的时间分布是由它们的光谱和光谱相位决定的，这一点很容易理解。为了优化和获得最短的脉冲持续时间，具有测量光谱和光谱相位的设备是绝对必要的。虽然在可见光和近红外光谱范围内存在许多用于超短激光脉冲诊断的技术并已商业化，但在红外和中红外光谱范围内的技术尚未广泛应用。近年来，INRS研究人员与学术界和工业界合作开发了两种红外和中红外超短脉冲诊断技术。第一种技术是基于多光子吸收的光谱仪，与目前的技术相比，它有潜力为红外激光器的光谱表征提供低成本的设备，具有更高的灵敏度和光谱分辨率。这将与few-cycle公司密切调查。第二种技术，FROSt，能够表征从可见光到中红外的脉冲，并且不需要相位匹配。因此，FROSt是表征能够产生单周期持续时间的倍频程激光脉冲的理想选择。对于单周期脉冲，另一个定义其时间结构的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的激光弹间波动。对于第二和第三项技术，在双方的支持下，INRS的研究人员将通过研究单周期脉冲的产生和特征，以及高重复率CEP的跟踪，将其推向极限。在该项目结束时，我们的技术将达到更高的TRL（从3到6），从而能够将其转让给加拿大公司，包括我们的工业合作伙伴。

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.