相关论文: Electro-optic sampling based characterization of b…
We demonstrate a cryogenic electro-optic sampling (EOS) setup that allows for the measurement of microwave signals at arbitrary positions on a cryogenic chip-scale device. We use a Josephson Arbitrary Waveform Synthesizer (JAWS) to generate…
Compact Free-Electron Lasers (FELs) offering broad, continuous spectral tunability are traditionally constrained by fixed-parameter magnetic structures and the necessity for high-energy electron beams. High-gain Harmonic Lasing (HL) has…
A technique to measure the band gap of dielectric materials with high refractive index by means of energy electron loss spectroscopy (EELS) is presented. The technique relies on the use of a circular (Bessel) aperture and suppresses…
In this paper we discuss the design choices and construction strategy of the tapered undulator system designed for a high energy extraction efficiency experiment in the ultraviolet region of the electromagnetic spectrum planned for…
Electro-optical detection has proven to be a valuable technique to study temporal profiles of THz pulses with pulse durations down to femtoseconds. As the Coulomb field around a relativistic electron bunch resembles the current profile,…
Combination of advanced high power laser technology, new acceleration methods and achievements in undulator development opens a way to build compact, high brilliance Free Electron Laser (FEL) driven by a laser wakefield accelerator (LWFA).…
The low-gain free-electron laser (FEL) oscillators are cutting-edge tools to produce fully coherent radiation in the spectral region from terahertz to vacuum ultraviolet, and potentially in hard X-ray. In this paper, it is proposed to…
We report a systematic experimental study of terahertz (THz) streaking structures for ultrafast characterization of relativistic, high-brightness electron beams. Horn-coupled waveguide geometries are investigated, enabling a comparative…
Most transmission and detection channels fail to faithfully support broadband wave packets because of physical limitations, like chromatic dispersion and absorption. We explore the case of lossy detection of ultrashort THz pulses using the…
High-power, continuously tunable narrowband terahertz (THz) sources are essential for advancing nonlinear optics, THz-driven material dynamics, and ultrafast spectroscopy. Conventional techniques typically impose a trade-off between pulse…
Using reflective cross-polarized 2D THz time-domain spectroscopy in the range of 1-12 THz, we follow the trajectory of the out-of-equilibrium electron population in the low-bandgap semiconductor InSb. The 2D THz spectra show a set of…
Electric field measurement in plasmas permits quantitative comparison between the experiment and the simulation in this study. An electro-optic (EO) sensor based on Pockels effect is demonstrated to measure wave electric fields in the…
Both theoretical and numerical analyses are conducted to investigate terahertz (THz) radiation emission from free-electron lasers. The angular and spectral characteristics of radiation are analytically evaluated leveraging Linenard Wiechert…
Ultrabroadband electro-optic sampling with few-cycle optical pulses is known to be an extremely sensitive technique to detect electric field amplitudes. By combining this method with dual-comb spectroscopy and with a new class of ultrafast…
We demonstrate optical coherent control of the emission direction of THz radiation. Femtosecond laser pulses are used to excite different types of ultrafast photocurrents along different directions in a bulk GaAs sample. The overall…
On the basis of an energy-recovery linac, a terahertz (THz) source with kilowatts average power is proposed in Shanghai, which will serve as an effective tool in material and biological sciences. In this paper, the physical design of two…
Terahertz electromagnetic radiation is extremely useful for numerous applications such as imaging and spectroscopy. Therefore, it is highly desirable to have an efficient table-top emitter covering the 1-to-30-THz window whilst being driven…
XFELs provide X-ray pulses with unprecedented peak brightness and ultrashort duration. They are usually driven by planar undulators, meaning that the output radiation is linearly polarized. For many experimental applications, however,…
Multidimensional optimization schemes for TW hard X-Ray free electron lasers are applied to the cases of transversely uniform and parabolic electron beam distributions and compared to examples of transversely Gaussian beams. The…
Terahertz (THz)-based electron manipulation has recently been shown to hold tremendous promise as a technology for manipulating and driving the next-generation of compact ultrafast electron sources. Here, we demonstrate an ultrafast…