Octave spanning gain by cavity enhanced optical parametric amplification

超宽带高功率激光技术为频率梳计量、阿秒科学和相对论光学等极端光学科学打开了大门。光参量啁啾脉冲放大（OPCPA）利用其宽的放大带宽和波长可调谐性，成为这些新兴研究领域的关键技术之一。该建议旨在开发一种新的基于腔的参量放大技术，该技术将允许倍频程跨越增益带宽和近量子限制的转换效率在~100 MHz的重复率，使用普通的泵浦源和OPA介质。这种技术，被称为腔增强的光学参量啁啾脉冲放大（C-OPCPA），在一个外腔中的泵浦脉冲的重复和被动整形，以有效地放大种子脉冲在非线性介质中。C-OPCPA采用增强的泵浦强度来补偿波矢量失配，在C-OPCPA几何结构中，这可以在一个倍频程以上的带宽上实现高效放大。拟议的研究将对具有增益和非线性损耗的腔动力学的基本理解做出重大贡献，并开发一种新方法，以便首次实现，C-OPCPA是一款重复频率约为100 MHz的高效率倍频程跨越参量放大器。更广泛的影响：C-OPCPA系统在许多科学和技术应用中非常有用，例如频率梳状放大和阿秒计量。所展示的C-OPCPA系统可以按比例放大到更高的平均功率，并作为高通量阿秒XUV脉冲产生通过高谐波产生的泵浦源。该项目还将为研究生、博士后研究人员和访问科学家提供教学工具。

Ultrabroadband high-power laser technology has opened a door to extreme optical sciences, such as frequency-comb metrology, attosecond science, and relativistic optics. Optical parametric chirped-pulse amplification (OPCPA) has become one of the key techniques of these emerging research areas employing the broad amplification bandwidth and wavelength tunability of optical parametric amplification (OPA). This proposal aims to develop a novel cavity-based parametric amplification technique that will allow octave-spanning gain bandwidth and near-quantum-limited conversion efficiency at ~100 MHz repetition rates, using ordinary pump sources and OPA media. This technique, referred to as cavity-enhanced optical parametric chirped-pulse amplification (C-OPCPA), recycles and passively reshapes pump pulses inside an external cavity to efficiently amplify seed pulses in a nonlinear medium. C-OPCPA employs the use of enhanced pump intensity to compensate for wave-vector mismatch, which, in the C-OPCPA geometry, can lead to efficient amplification at bandwidths of more than one octave.Intellectual Merit: The proposed research will make significant contributions to the fundamental understanding of cavity dynamics with gain and nonlinear loss and develop a new method in order to achieve, for the first time, a highly efficient octave-spanning parametric amplifier at ~100 MHz repetition rate.Broader Impact: C-OPCPA systems are very useful for many scientific and technological applications, such as frequency-comb amplification and attosecond metrology. The C-OPCPA system to be demonstrated can be scaled up to much higher average power and serve as a pump source for high-flux attosecond XUV pulse generation via high-harmonic generation. The project will also provide a teaching vehicle for graduate students, postdoctoral researchers, and visiting scientists.