Ultrashort high quality electron beam from laser wakefield accelerator using two-step plasma density profile

Area of Science:

• Plasma Physics
• Accelerator Physics
• Quantum Electronics

Background:

• Laser wakefield acceleration (LWFA) is a promising method for generating high-quality electron beams.
• Conventional LWFA often faces challenges in controlling beam quality and duration.
• Radio-frequency (RF) linac injectors are known for producing high-quality electron beams.

Purpose of the Study:

• To integrate RF linac injector principles into LWFA using a two-step plasma density profile.
• To generate ultrashort, high-quality electron beams with reduced energy spread and bunch length.
• To explore the potential for generating intense coherent terahertz radiation.

Main Methods:

• Utilizing a two-step plasma density profile in the LWFA.
• Incorporating the physics principles of conventional RF linac injectors into the LWFA design.
• Performing simulations to observe the electron beam characteristics and generated radiation.

Main Results:

• Successfully generated an ultrashort, high-quality electron beam with an RMS energy spread of 1.9% and an RMS bunch length of 2 fs.
• Demonstrated the generation of ultrashort intense terahertz coherent radiation with 200 MW power and 2 fs duration.
• Validated the effectiveness of the two-step plasma density profile in enhancing LWFA performance.

Conclusions:

• The proposed LWFA with a two-step plasma density profile effectively generates ultrashort, high-quality electron beams.
• This approach offers a pathway to produce intense terahertz radiation.
• The integration of RF linac injector physics into LWFA shows significant potential for future accelerator applications.