Abstract-Stable and Scalable Multistage Terahertz-Driven Particle Accelerator

 

Heng Tang, Lingrong Zhao, Pengfei Zhu, Xiao Zou, Jia Qi, Ya Cheng, Jiaqi Qiu, Xianggang Hu, Wei Song, Dao Xiang, and Jie Zhang

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.127.074801?ft=1

Particle accelerators that use electromagnetic fields to increase a charged particle’s energy have greatly advanced the development of science and industry since invention. However, the enormous cost and size of conventional radio-frequency accelerators have limited their accessibility. Here, we demonstrate a miniaccelerator powered by terahertz pulses with wavelengths 100 times shorter than radio-frequency pulses. By injecting a short relativistic electron bunch to a 30-mm-long dielectric-lined waveguide and tuning the frequency of a 20-period terahertz pulse to the phase-velocity-matched value, precise and sustained acceleration for nearly 100% of the electrons is achieved with the beam energy spread essentially unchanged. Furthermore, by accurately controlling the phase of two terahertz pulses, the beam is stably accelerated successively in two dielectric waveguides with close to 100% charge coupling efficiency. Our results demonstrate stable and scalable beam acceleration in a multistage miniaccelerator and pave the way for functioning terahertz-driven high-energy accelerators.

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Abstract-Terahertz oscilloscope for recording time information of ultrashort electron beams

Lingrong Zhao, Zhe Wang, Heng Tang, Rui Wang, Yun Cheng, Chao Lu, Tao Jiang, Pengfei Zhu, Long Hu, Wei Song, Huida Wang, Jiaqi Qiu, Roman Kostin, Chunguang Jing, Sergey Antipov, Peng Wang, Jia Qi, Ya Cheng, Dao Xiang, and Jie Zhang

https://journals.aps.org/prl/accepted/d407dY16M5819b51b9d98708b359b7042e3e658c9

We propose and demonstrate a Terahertz (THz) oscilloscope for recording time information of an ultrashort electron beam. By injecting a laser-driven THz pulse with circular polarization into a dielectric tube, the electron beam is swept helically such that the time information is uniformly encoded into the angular distribution that allows one to characterize both the temporal profile and timing jitter of an electron beam. The dynamic range of the measurement in such a configuration is significantly increased compared to deflection with a linearly polarized THz pulse. With this THz oscilloscope, nearly 50-fold longitudinal compression of a relativistic electron beam to about 15 fs (rms) is directly visualized with its arrival time determined with 3 fs accuracy. This technique bridges the gap between streaking of photoelectrons with optical lasers and deflection of relativistic electron beams with radio-frequency deflectors, and should have wide applications in many ultrashort electron beam based facilities.

Abstract-Terahertz Streaking of Few-Femtosecond Relativistic Electron Beams

Lingrong Zhao, Zhe Wang, Chao Lu, Rui Wang, Cheng Hu, Peng Wang, Jia Qi, Tao Jiang, Shengguang Liu, Zhuoran Ma, Fengfeng Qi, Pengfei Zhu, Ya Cheng, Zhiwen Shi, Yanchao Shi, Wei Song, Xiaoxin Zhu, Jiaru Shi, Yingxin Wang, Lixin Yan, Liguo Zhu, Dao Xiang, and Jie Zhan

https://journals.aps.org/prx/abstract/10.1103/PhysRevX.8.021061

Streaking of photoelectrons with optical lasers has been widely used for temporal characterization of attosecond extreme ultraviolet pulses. Recently, this technique has been adapted to characterize femtosecond x-ray pulses in free-electron lasers with the streaking imprinted by far-infrared and terahertz (THz) pulses. Here, we report successful implementation of THz streaking for time stamping of an ultrashort relativistic electron beam, whose energy is several orders of magnitude higher than photoelectrons. Such an ability is especially important for MeV ultrafast electron diffraction (UED) applications, where electron beams with a few femtosecond pulse width may be obtained with longitudinal compression, while the arrival time may fluctuate at a much larger timescale. Using this laser-driven THz streaking technique, the arrival time of an ultrashort electron beam with a 6-fs (rms) pulse width has been determined with 1.5-fs (rms) accuracy. Furthermore, we have proposed and demonstrated a noninvasive method for correction of the timing jitter with femtosecond accuracy through measurement of the compressed beam energy, which may allow one to advance UED towards a sub-10-fs frontier, far beyond the approximate 100-fs (rms) jitter.

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Abstract-Terahertz streaking of few-femtosecond relativistic electron beams

Lingrong Zhao, Zhe Wang, Chao Lu, Rui Wang, Cheng Hu, Peng Wang, Jia Qi, Tao Jiang, Shengguang Liu, Zhuoran Ma, Fengfeng Qi, Pengfei Zhu, Ya Cheng, Zhiwen Shi, Yanchao Shi, Wei Song, Xiaoxin Zhu, Jiaru Shi, Yingxin Wang, Lixin Yan, Liguo Zhu, Dao Xiang,  Jie Zhang,

https://journals.aps.org/prx/accepted/d8075K71A261f001129c7ce70c632d2221b6fd030

Streaking of photoelectrons with optical lasers has been widely used for temporal characterization of attosecond extreme ultraviolet pulses. Recently, this technique has been adapted to characterize femtosecond x-ray pulses in free-electron lasers with the streaking imprinted by far-infrared and Terahertz (THz) pulses. Here, we report successful implementation of THz streaking for time-stamping of an ultrashort relativistic electron beam of which the energy is several orders of magnitude higher than photoelectrons. Such ability is especially important for MeV ultrafast electron diffraction (UED) applications where electron beams with a few femtosecond pulse width may be obtained with longitudinal compression while the arrival time may fluctuate at a much larger time scale. Using this laser-driven THz streaking technique, the arrival time of an ultrashort electron beam with 6 fs (rms) pulse width has been determined with 1.5 fs (rms) accuracy. Furthermore, we have proposed and demonstrated a non-invasive method for correction of the timing jitter with femtosecond accuracy through measurement of the compressed beam energy, which may allow one to advance UED towards sub-10 fs frontier far beyond the $\sim$100 fs (rms) jitter.