Tabletop Ultrafast Laser-Plasma X-ray Dynamic Diagnostics System

Using a tabletop femtosecond laser and a specially designed target chamber, we bring FemtoX, a tabletop ultrafast X-ray pulse with a pulse width of less than 100 femtoseconds (fs), into small and medium-sized laboratories. In addition, complete solutions and diagnostic systems can be designed and provided according to customer application requirements.

After nearly two decades of development, the laser-plasma pulsed ultrafast X-ray radiation source has been widely applied in numerous international laboratories, demonstrating characteristics of ultra-small size, ultra-brightness, high signal-to-noise ratio, and high stability. It holds significant application value in the study of ultrafast processes in matter and high-resolution imaging. Combined with the low cost of the system, it has become an effective complement to synchrotron radiation sources in the ultrafast domain.

In particular, the current third-generation synchrotron radiation has a time resolution on the order of hundreds of picoseconds (ps), which is insufficient for studying rapid processes occurring on sub-picosecond (sub-ps) or even femtosecond timescales, such as chemical bond breaking and formation, and lattice vibrations. Chemical reactions and phase transitions driven by atomic motion occur on sub-ps timescales, and traditional ultrafast spectroscopy can only provide information on electronic state transitions, not transient structural changes. In contrast, characterization methods based on ultrafast X-rays, such as ultrafast X-ray diffraction (UXRD) and ultrafast X-ray absorption spectroscopy (UXAS), are more effective. Because the laser pulses emitted by femtosecond lasers are ultra-short (pulse widths on the order of tens of fs) and ultra-intense (high energy per pulse), the X-ray pulse width generated during laser-target interaction is comparable to the laser pulse width. Combined with the natural temporal synchronization between the X-rays and the driving laser, FemtoX can be used in pump-probe experiments, providing dynamic analysis of matter with sub-ps or even fs time resolution.

Furthermore, the source size of FemtoX largely depends on the laser spot size. In the current system, the laser spot is approximately 5 micrometers (µm) (FWHM), enabling an X-ray source with a focal spot size on the order of 10 µm. Due to its X-ray generation mechanism, which differs from that of conventional X-ray tubes, it achieves both a small focal spot and high X-ray output power. This offers significant application prospects in fields requiring high spatial resolution and spatial coherence, such as X-ray transmission imaging and phase-contrast imaging.