Terahertz emission in tenuous gases irradiated by ultrashort laser pulses

• 作 者: 王伟民 盛政明 武慧春 陈民 李春 张杰 K. Mima
• 机 构: Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, CAS,Department of Phy
• 出 处: 中国物理C
• 发表日期: 2004年期
• 关键词: gases irradiated longitudinal currents terahertz scaling ionization normalized a

Mechanism of terahertz (THz) pulse generation in gases irradiated by ultrashort laser pulses is investigated theoretically. Quasi-static transverse currents produced by laser field ionization of gases and the longitudinal modulation in formed plasmas are responsible for the THz emission at the electron plasma frequency, as demonstrated by particle-in-cell simulations including field ionization. The THz field amplitude scaling with the laser amplitude within a large range is also discussed.

Mechanism of terahertz (THz) pulse generation in gases irradiated by ultrashort laser pulses is considered theoretically. Quasi-static transverse currents produced by laser field ionization of gases and the longitudinal modulation in formed plasmas are responsible for the THz emission at the electron plasma frequency, as demonstrated by particle-in-cell simulations including field ionization. The THz field amplitude scaling with the laser amplitude within a large range is also discussed.