Related Experiment Video
Updated: May 26, 2026
10:17
20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier
Published on: July 12, 2017
High-gain harmonic-generation free-electron laser seeded by harmonics generated in gas
M Labat1, M Bellaveglia, M Bougeard
1ENEA C.R. Frascati, Via E. Fermi, 45 00044 Frascati, Roma, Italy.
Physical Review Letters
|December 21, 2011
Summary
Seeding a cascaded free-electron laser (FEL) with gas-generated harmonics amplified its performance at shorter wavelengths. This study reports the first operation of such a high-gain harmonic-generation FEL, optimizing laser output.
Area of Science:
- Physics
- Laser Science
- Quantum Optics
Background:
- Seeding a free-electron laser (FEL) amplifier improves longitudinal coherence and reduces saturation length.
- Cascaded FELs operating in the high-gain harmonic-generation (HGHG) regime can extend seeding benefits to shorter wavelengths.
- Harmonic generation in gas is a viable method for seeding FELs.
Purpose of the Study:
- To report the first operation of a HGHG FEL seeded with gas-generated harmonics.
- To amplify and up-convert the third harmonic of a Ti:sapphire laser to its second harmonic (133 nm) using a cascaded FEL.
- To study the transition between coherent harmonic generation and superradiant regimes and optimize FEL performance.
Main Methods:
- Utilizing a cascaded FEL configuration with a variable number of modulators and radiators.
- Seeding the FEL with the third harmonic of a Ti:sapphire laser generated in a gas cell.
- Investigating the transition between coherent harmonic generation and superradiant regimes by varying the number of modulators and radiators.
Main Results:
- Successful amplification and up-conversion of the third harmonic to its second harmonic at 133 nm.
- Demonstration of the first operation of a HGHG FEL seeded with gas-generated harmonics.
- Optimization of laser performance by adjusting the number of modulators and radiators, studying the transition between coherent and superradiant regimes.
Conclusions:
- Cascaded FELs seeded with gas-generated harmonics are effective for generating short-wavelength radiation.
- The HGHG regime in cascaded FELs allows for extending seeding benefits to shorter wavelengths.
- Optimizing the number of modulators and radiators is crucial for controlling the FEL regime and enhancing performance.
Related Concept Videos
01:10Generating Electromagnetic Radiations
The German physicist Heinrich Hertz (1857–1894) was the first to generate and detect certain types of electromagnetic waves in the laboratory. Starting in 1887, he performed a series of experiments that confirmed the existence of electromagnetic waves and verified that they travel at the speed of light. Hertz used an alternating-current RLC (resistor-inductor-capacitor) circuit that resonated at a known frequency and connected it to a loop of wire. High voltages induced across the gap in the...
01:19Inductively Coupled Plasma Atomic Emission Spectroscopy: Principle
Inductively coupled plasma (ICP) is the most widely used plasma source in atomic emission spectroscopy (AES), also known as Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The ICP source, or torch, consists of three concentric quartz tubes with argon gas flowing through them. A spark from a Tesla coil initiates the ionization of argon, generating a high-temperature plasma.
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...