Abstract- Polarization-tunable terahertz radiation in the high-field regime

Polarization-tunable terahertz radiation in the high-field regime 

Zi-Yu Chen and Alexander Pukhov

https://www.osapublishing.org/ol/abstract.cfm?uri=ol-41-11-2660

Polarization control of terahertz (THz) pulses in the high-field regime is a challenging subject. Here we propose and numerically demonstrate an all-optical scheme to generate a polarization-tunable high-field THz source based on relativistic laser plasma interactions. By adjusting the polarization state of the driving laser, collective oscillation of the plasmas can be steered. Phase difference between the laser field components is inherited in the plasma dynamics, as well as in the resulting THz generation process. Single-cycle extremely intense THz pulses with field strength ∼  GV/cm can be generated. The THz polarization state can be tuned from linear through elliptical to circular by changing the polarization state of the driving laser.

© 2016 Optical Society of America

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Abstract-High field terahertz pulse generation from plasma wakefield driven by tailored laser pulses

Zi-Yu Chen

National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China 

http://apl.aip.org/resource/1/applab/v102/i24/p241104_s1?isAuthorized=no

A scheme to generate high field terahertz (THz) pulses by using tailored laser pulses interaction with a gas target is proposed. The laser wakefield based THz source is emitted from the asymmetric laser shape induced plasma transverse transient net currents. Particle-in-cell simulations show that THz emission with electric filed strength over 1 GV/cm can be obtained with incident laser at 1×10¹⁹ W/cm² level, and the corresponding energy conversion efficiency is more than 10⁻⁴. The intensity scaling holds up to high field strengths. Such a source also has a broad tunability range in amplitude, frequency spectra, and temporal shape.

© 2013 AIP Publishing LLC