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Tunable High-Intensity Electron Bunch Train Production Based on Nonlinear Longitudinal Space Charge Oscillation
Zhen Zhang1, Lixin Yan1, Yingchao Du1
1Department of Engineering Physics, Tsinghua University, Beijing 100084, China.
Physical Review Letters
|May 21, 2016
Summary
Researchers generated high-intensity electron bunches with tunable spacing for terahertz (THz) radiation. This breakthrough enables the creation of powerful, narrow-band THz sources and advanced particle acceleration.
Area of Science:
- Physics
- Accelerator Physics
- Quantum Electronics
Background:
- Generating high-intensity electron bunches is crucial for advanced light sources.
- Controlling electron beam properties is key to producing coherent terahertz (THz) radiation.
Purpose of the Study:
- To experimentally produce and measure high-intensity electron bunch trains with tunable picosecond spacing.
- To achieve narrow-band coherent THz radiation generation from these electron bunches.
Main Methods:
- Imposing initial density modulation on a relativistic electron beam.
- Controlling charge density and using a magnetic chicane for bunch compression.
- Tuning the launching phase of a radio-frequency gun to vary bunch spacing.
Main Results:
- Observed density spikes with several-hundred-ampere peak current for the first time.
- Demonstrated continuous tuning of bunch train spacing.
- Measured narrow-band coherent THz radiation with microjoule-level energies (0.5–1.6 THz).
Conclusions:
- The study successfully generated tunable, high-intensity electron bunches.
- Achieved narrow-band coherent THz radiation generation with tunable frequency.
- Results support the development of millijoule-level THz sources and high-gradient acceleration.
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