Attosecond betatron radiation pulse train.

Area of Science:

• Physics
• Laser-driven particle acceleration
• X-ray science

Background:

• High-intensity X-ray sources are crucial for science, technology, and medicine.
• Betatron radiation from laser-plasma accelerators produces femtosecond X-ray pulses from micrometer sources.
• Current sources offer limited temporal resolution for ultrafast phenomena.

Purpose of the Study:

• To demonstrate enhanced temporal resolution of X-ray sources.
• To achieve sub-femtosecond X-ray pulse generation.
• To explore applications in ultrafast process sampling.

Main Methods:

• Particle-in-cell simulations were employed.
• Spatial modulation of relativistic electron bunches was simulated.
• Interaction with a co-propagating laser beam induced modulation.

Main Results:

• Temporal resolution was enhanced by an order of magnitude.
• Generation of a train of equidistant sub-femtosecond X-ray pulses was achieved.
• Pulse train spacing is tunable via modulation laser wavelength.

Conclusions:

• The proposed method significantly improves X-ray source temporal resolution.
• The technique is achievable with current experimental technologies.
• Potential for stroboscopic sampling of fundamental ultrafast processes exists.