The time-frequency degree of freedom is a powerful resource for implementing high-dimensional quantum information processing. In particular, field-orthogonal pulsed temporal modes offer a flexible framework compatible with both long-distance fiber networks and integrated waveguide devices. In order for this architecture to be fully utilized, techniques to reliably generate diverse quantum states of light and accurately measure complex temporal waveforms must be developed. To this end, nonlinear processes mediated by spectrally shaped pump pulses in group-velocity engineered waveguides and crystals provide a capable toolbox. In this review, we examine how tailoring the phase-matching conditions of parametric downconversion and sum-frequency generation allows for highly pure single-photon generation, flexible temporal-mode entanglement, and accurate measurement of time-frequency photon states. We provide an overview of experimental progress towards these goals and summarize challenges that remain in the field.

中文翻译：

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利用脉冲时间模式编码量身定制量子光学的非线性过程

时频自由度是实现高维量子信息处理的强大资源。特别是，正交场脉冲时间模式提供了与长距离光纤网络和集成波导设备兼容的灵活框架。为了充分利用此体系结构，必须开发可靠地产生光的多种量子态并准确测量复杂的时间波形的技术。为此，在群速度工程波导和晶体中由频谱形状的泵浦脉冲介导的非线性过程提供了一个功能强大的工具箱。在这篇综述中，我们研究了如何调整参数下变频和总和频率生成的相位匹配条件，可以实现高纯度的单光子生成，灵活的时模纠缠，并精确测量时频光子状态。我们概述了实现这些目标的实验进展，并总结了该领域中仍然存在的挑战。