Amplified bursts of laser pulses are sought for various machining, deposition, spectroscopic, and strong-field applications. Standard frequency- and time-domain techniques for pulse division become inadequate when intraburst repetition rates reach the terahertz (THz) range as a consequence of inaccessible spectral resolution, requirement for interferometric stability, and collapse of the chirped-pulse amplification (CPA) concept due to the loss of usable bandwidth needed for safe temporal stretching. Avoiding the burst amplification challenge and resorting to lossy post-division of an isolated laser pulse after CPA leaves the limitations of frequency- and time-domain techniques unsolved. In this Letter, we demonstrate an approach that successfully combines amplitude and phase shaping of THz bursts, formed using the Vernier effect, with active stabilization of spectral modes and efficient energy extraction from a CPA regenerative amplifier. As proof of concept, the amplified bursts of femtosecond near-infrared pulses are down-converted into tunable THz-frequency pulses via optical rectification.

中文翻译：

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chi脉冲激光放大中太赫兹脉冲的可编程生成

寻找用于各种机加工，沉积，光谱学和强场应用的放大的激光脉冲猝发。当突发内重复频率达到太赫兹（THz）范围时，由于无法获得频谱分辨率，要求干涉仪稳定性以及chi脉冲放大（CPA）概念崩溃，导致脉冲划分的标准频域和时域技术变得不充分。安全时间扩展所需的可用带宽的损失。避免了突发放大挑战，并在CPA之后求助于隔离激光脉冲的有损后分频，从而解决了频域和时域技术的局限性。在这封信中，我们演示了一种方法，该方法成功地结合了使用游标效应形成的太赫兹脉冲的幅度和相位整形，主动稳定频谱模式，并从CPA再生放大器中高效提取能量。作为概念验证，飞秒近红外脉冲的放大脉冲串通过光学整流被下转换为可调的THz频率脉冲。