以GHz重复频率驱动自旋电子太赫兹发射器
Driving Spintronic Terahertz Emitters at GHz Repetition Rates
- The University of Manchester（曼彻斯特大学）
- The Cockcroft Institute, Sci-Tech Daresbury（科克沃尔研究所，达尔斯伯里科技）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究利用异步光学采样太赫兹时域光谱仪，发现高重复频率激光驱动自旋电子太赫兹发射器会导致永久性热损伤，而采用高热导率衬底可将损伤阈值提高三个数量级，实现稳定发射。
AI中文摘要：
自旋电子太赫兹发射器（STEs）是多功能的太赫兹（THz）频率辐射源，能够提供高电场强度和无间隙带宽，覆盖太赫兹波段（0.1-30 THz）。此外，它们生产成本低，并且易于在各种光学装置中使用。然而，其更广泛应用的一个障碍是近期报道的当以高重复频率激光驱动时，光学注量损伤阈值会降低。在此，我们使用异步光学采样（ASOPS）太赫兹时域光谱仪（THz-TDS）来实时观察当以1 GHz重复频率激光驱动时太赫兹信号的退化。我们证明太赫兹发射的损失是永久性的，并且很可能是对STE结构的热损伤所致。然而，通过利用具有高热导率的衬底，观察到损伤阈值提高了超过三个数量级，从而首次实现了在高重复频率激光驱动下STE的稳定发射。
英文摘要：
Spintronic terahertz emitters (STEs) are versatile sources of terahertz (THz) frequency radiation that offer high electric field strengths and gap-free bandwidths covering the THz (0.1-30 THz) band. In addition, they are low-cost to produce and easy to use in a variety of optical setups. However, an obstacle to their wider applicability is the recently reported decrease in optical fluence damage threshold when driven with high-repetition-rate lasers. Here, we use an asynchronous optical sampling (ASOPS) THz time-domain spectrometer (THz-TDS) to observe the degradation of the THz signal in real-time when driven by a 1 GHz repetition-rate laser. We demonstrate that the loss of THz emission is permanent and is likely the result of thermal damage to the STE structure. However, by utilizing substrates with high thermal conductivities, an increase of the damage threshold of over three orders of magnitude is observed enabling stable emission from a STE for the first time when driven by a high-repetition-rate laser.
