Frequency Resolved Optical Switching (FROSt) for the temporal characterization of ultrafast infrared/mid-infrared lasers (Phase 1)

超快激光器市场在2019年的价值为44.4亿美元，预计到2024年将达到131.2亿美元。由于超快激光器的市场正在快速增长，因此对激光诊断的需求也将相应增加。对于整个激光器类别，能够测量脉冲时间轮廓的仪器是绝对必要的，无论是获得最短的脉冲持续时间，还是获得特定的所需脉冲形状。因此，将高度需要能够测量激光脉冲的光谱和光谱相位的光学设备（可以经由傅立叶变换从其检索I（t））。虽然许多技术已商业化用于可见光和近红外光谱范围，但它们不适用于红外和中红外范围。 近年来，INRS的研究人员和合作者开发了一种创新技术，用于测量红外和中红外光谱范围内的超短脉冲。这种用于超快激光系统的计量被称为频率分辨光开关（FROSt），并且已经能够表征来自低重复率激光系统的0.8至10微米中心波长的超短脉冲。这使得该技术成为光学参量放大器（OPA）产生的脉冲的完整时间表征的理想选择，该技术正被学术界、政府和工业研究人员广泛使用。然而，为了将这项技术推向市场，我们需要定义它是否可以用于高重复率激光系统的时间表征，例如由高重复率镱激光系统（~ 100 kHz）泵浦的OPA。因此，在这个I2 I项目的背景下，我们将开发一个原型，旨在表征这种高重复率可调谐IR/中IR激光源。为此，我们之前需要研究FROSt所需的通量，以及它可以运行的最大重复率。此外，为了说服潜在用户采用这种计量方法，我们将开发一种软件，该软件既可以采集FROSt测量值，也可以重建激光脉冲的时间轮廓。最后，我们将访问感兴趣的用户，以验证开发的FROSt设备的独特功能。

The market for ultrafast lasers was representing a value of 4.44B US$ in 2019 and is expected to reach 13.12B$ by 2024. Since the market for ultrafast lasers is growing rapidly, the need for laser diagnostics will increase accordingly. For this entire category of lasers, instruments capable to measure the pulse temporal profile are absolutely essential, whether it is to get the shortest pulse duration, or to obtain a specific desired pulse shape. Therefore, optical devices able to measure the spectra and the spectral phase of laser pulses (from which I(t) can be retrieved via a Fourier transform) will be in high demand. While many technologies are commercialized for the visible and near-IR spectral range, they are not adapted for the IR and mid-IR range. Over the recent years, INRS researchers and collaborators have developed an innovative technology to measure ultrashort pulses in the IR and mid-IR spectral range. This metrology for ultrafast laser systems is named Frequency Resolved Optical Switching (FROSt) and has already enabled to characterize ultrashort pulses from 0.8 to 10 microns central wavelength from a low repetition rate laser system. This makes this technology ideal for the complete temporal characterization of pulses derived from optical parametric amplifiers (OPA), which are becoming widely used by academic, government, and industrial researchers. However, to push this technology on the market, we need to define whether it can be used for the temporal characterization of high repetition rate laser systems such as OPAs pumped by high repetition rate Ytterbium laser systems (~100kHz). Thus, in the context of this I2I project, we will develop a prototype intended to characterize such high repetition rate tunable IR/mid-IR laser sources. For this, we previously need to investigate the fluence required for FROSt, and the maximum repetition rate at which it can operate. Furthermore, to convince potential users to adopt this metrology, we will develop a software that performs both the acquisition of the FROSt measurements as well as the reconstruction of the temporal profile of the laser pulses. Finally, we will visit interested users to validate the unique capabilities of the developed FROSt device.