Enhancement and modulation of terahertz radiation by multi-color laser pulses<xref rid="cpb_27_8_084209_fn1" ref-type="fn">*</xref><fn id="cpb_27_8_084209_fn1"><label>*</label><p>Project supported by the National Natural Science Foundation of China (Grant No. 11604205) and the Talent Program of Shanghai University of Engineering Science, China.</p></fn>

Enhancement and modulation of terahertz radiation by multi-color laser pulses**

Project supported by the National Natural Science Foundation of China (Grant No. 11604205) and the Talent Program of Shanghai University of Engineering Science, China.

Pei Min-Jie¹, Lu Chen-Hui^{2, †}, Wang Xian-Wei³, Sun Zhen-Rong¹, Zhang Shi-An^{1, ‡}

(color online) Time-dependent increasing rate of electron density dNe(t)/dt for the harmonic five-color laser pulse (blue dashed line) and the uncommon five-color laser pulse with the replaceable wavelength of λ₅ = 1200 nm (red solid line) in the pulse duration, and the corresponding electron velocity v_f(t_n) for the harmonic (blue squares) and uncommon (red circles) laser pulse.