학술논문

Terahertz emission from two-plasmon-decay induced transient currents in laser-solid interactions
Document Type
article
Source
Physics of Plasmas. 23(1)
Subject
Atomic
Molecular
Nuclear
Particle and Plasma Physics
Astronomical and Space Sciences
Classical Physics
Fluids & Plasmas
Atomic
Molecular
Nuclear
Particle and Plasma Physics
Language
Abstract
© 2016 AIP Publishing LLC. We have studied the generation of terahertz (THz) radiation via the interaction of intense femtosecond laser pulses with solid targets at a small incidence angle. It is found that preplasma with a moderate density gradient can enhance the emission. We also observe saturation of the THz output with the driving laser energy. We find that THz emission is closely related to the 3/2 harmonics of the driving laser. Particle-in-cell simulations indicate that under the present experimental conditions, the THz emission could be attributed to the transient currents at the plasma-vacuum interface, mainly formed by the two-plasmon-decay instability.