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Updated: Jul 20, 2026
10:52
Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Electron acceleration by a self-diverging intense laser pulse
K P Singh1, D N Gupta, V K Tripathi
1Department of Physics, Indian Institute of Technology, New Delhi-110016, India. k_psingh@yahoo.com
Summary
Laser pulses can accelerate electrons in gas. Tunnel ionization defocuses the laser, causing electrons to gain net energy from the pulse
Area of Science:
- Plasma physics
- Laser-matter interactions
Background:
- Electron acceleration is crucial for various applications.
- Laser-driven acceleration offers a compact alternative to traditional methods.
Purpose of the Study:
- To investigate electron acceleration using a Gaussian laser pulse in a vacuum-gas interaction region.
- To understand the role of tunnel ionization in electron energy gain.
Main Methods:
- Simulating electron acceleration by a Gaussian laser pulse.
- Modeling the interaction in a vacuum followed by a neutral gas medium.
- Analyzing the effects of tunnel ionization and ponderomotive forces.
Main Results:
- Tunnel ionization of gas defocuses the laser pulse.
- Electrons experience net energy gain due to asymmetric ponderomotive forces.
- Higher initial gas density and laser intensity enhance electron acceleration.
Conclusions:
- Optimizing gas density and laser parameters is key for efficient electron acceleration.
- Laser pulse defocusing via tunnel ionization is a viable mechanism for electron energy gain.
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