Enhancement of terahertz wave generation by cascaded χ(2) processes in LiNbO3
Enhancement of terahertz wave generation by cascaded χ(2) processes in LiNbO3
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DOI：
10.1364/josab.26.00a101
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发表时间：
2009-09-01
影响因子：
1.9
通讯作者：
Tanaka, Koichiro
中科院分区：
文献类型：
--
作者：
Jewariya, Mukesh;Nagai, Masaya;Tanaka, Koichiro
据我们所知，我们证明了一种新的太赫兹（THz）电磁波的产生过程，通过非共线的χ（2）过程中的铌酸锂与相位波前控制的飞秒钛：蓝宝石激光脉冲。系统的太赫兹电场和激发传输通过铌酸锂晶体在不同的激发功率的测量表明，太赫兹电场的最大振幅非线性增加的临界输入功率以上。这种光整流效率的提高归因于通过发射的太赫兹波经由电光（EO）相位调制的激发脉冲形状的失真。实际上，太赫兹波和激发脉冲的谱线形状在阈值以上变宽，并且它们通过在频域中使用等效一维映射耦合方程的数值模拟很好地再现。该发电方案显示出进一步发电效率的潜在优化。(C)2009年美国光学学会
We demonstrate, to the best of our knowledge, a novel generation process of a terahertz (THz) electromagnetic wave via a noncollinear chi((2)) process in LiNbO3 with a phase-front-controlled femtosecond Ti:sapphire laser pulse. Systematic measurements of both the THz electric field and the excitation transmitted through an LiNbO3 crystal at different excitation powers show that the maximum amplitude of the THz electric field increases nonlinearly above the critical input powers. This enhancement of optical rectification efficiency is attributed to the distortion of the excitation pulse shape via electro-optic (EO) phase modulation by the emitted THz wave. Actually, spectral line shapes of both the THz wave and the excitation pulse become broadened above the threshold, and they are well reproduced by numerical simulations with equivalent one-dimensionally mapped coupled equations in the frequency domain. This generation scheme shows potential optimization of further generation efficiency. (C) 2009 Optical Society of America