Dual-frequency terahertz radiation from air-plasma filaments produced with two-color lasers in air has been demonstrated experimentally. When a focusing lens is tilted for a few degrees, it is shown that the laser filament evolves from a single one to two sub-filaments. Two independent terahertz sources emitted from the sub-filaments with different frequencies and polarizations are identified, where the frequency of terahertz waves from the trailing sub-filament is higher than that from the leading sub-filament.
- dual-frequency terahertz radiation
- air-plasma filaments
- independent terahertz sources
Zhang, Z., Chen, Y., Yang, L., Yuan, X., Liu, F., Chen, M., Xu, J., Sheng, Z., & Zhang, J. (2014). Dual-frequency terahertz emission from splitting filaments induced by lens tilting in air. Applied Physics Letters, 105(10), . https://doi.org/10.1063/1.4895720