Baek In Hyung, Kim Hyun Woo, Bark Hyeon Sang, Jang Kyu-Ha, Park Sunjeong, Shin Junho, Kim Young Chan, Kim Mihye, Oang Key Young, Lee Kitae, Rotermund Fabian, Vinokurov Nikolay A, Jeong Young Uk
Korea Atomic Energy Research Institute (KAERI), Daejeon, 34057, Republic of Korea.
University of Science and Technology (UST), Daejeon, 34113, Republic of Korea.
Nat Commun. 2021 Nov 25;12(1):6851. doi: 10.1038/s41467-021-27256-x.
The deflection of charged particles is an intuitive way to visualize an electromagnetic oscillation of coherent light. Here, we present a real-time ultrafast oscilloscope for time-frozen visualization of a terahertz (THz) optical wave by probing light-driven motion of relativistic electrons. We found the unique condition of subwavelength metal slit waveguide for preserving the distortion-free optical waveform during its propagation. Momentary stamping of the wave, transversely travelling inside a metal slit, on an ultrashort wide electron bunch enables the single-shot recording of an ultrafast optical waveform. As a proof-of-concept experiment, we successfully demonstrated to capture the entire field oscillation of a THz pulse with a sampling rate of 75.7 TS/s. Owing to the use of transversely-wide and longitudinally-short electron bunch and transversely travelling wave, the proposed "single-shot oscilloscope" will open up new avenue for developing the real-time petahertz (PHz) metrology.
带电粒子的偏转是直观呈现相干光电磁振荡的一种方式。在此，我们展示了一种实时超快示波器，通过探测相对论电子的光驱动运动来对太赫兹（THz）光波进行时间冻结可视化。我们发现了亚波长金属狭缝波导在其传播过程中保持无失真光波形的独特条件。在超短宽电子束上瞬间记录在金属狭缝内横向传播的波，能够单次记录超快光波形。作为概念验证实验，我们成功地以75.7 TS/s的采样率捕获了太赫兹脉冲的整个场振荡。由于使用了横向宽且纵向短的电子束以及横向行波，所提出的“单次示波器”将为开发实时拍赫兹（PHz）计量学开辟新途径。
