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arXiv · 1504.02291

Tunable Circularly Polarized Terahertz Radiation from Magnetized Gas Plasma

W. -M. Wang·P. Gibbon·Z. -M. Sheng·Y. -T. Li
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Abstract

It is shown, by simulation and theory, that circularly or elliptically polarized terahertz radiation can be generated when a static magnetic (B) field is imposed on a gas target along the propagation direction of a two-color laser driver. The radiation frequency is determined by $\sqrt{\omega_p^2+{\omega_c^2}/{4}} + {\omega_c}/{2}$, where $\omega_p$ is the plasma frequency and $\omega_c$ is the electron cyclotron frequency. With the increase of the B field, the radiation changes from a single-cycle broadband waveform to a continuous narrow-band emission. In high-B-field cases, the radiation strength is proportional to $\omega_p^2/\omega_c$. The B field provides a tunability in the radiation frequency, spectrum width, and field strength.

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W. -M. Wang, P. Gibbon, Z. -M. Sheng, Y. -T. Li. 2015-04-09. Tunable Circularly Polarized Terahertz Radiation from Magnetized Gas Plasma. https://doi.org/10.1103/physrevlett.114.253901

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