倒V形四能级亚飞秒极化拍的三光子吸收和色散

基于孪生色锁噪声场的互相关效应，从理论上研究了倒V形(RV)四能级飞秒量级差频极化拍与极化拍中五阶非线性极化率，并提出了用一种相位敏感的方法来研究多能级原子相干造成的三光子六波混频过程.在抽泵光束为窄带末端情况下，场关联对信号和极化率的影响都很弱，在非窄带情况下，场关联会使极化强度自相干信号和极化拍信号产生关于零延时的不对称性和时域扫描上的辐射与物质失谐阻尼振荡(RDO)，而极化率会产生频域扫描上的RDO振荡.参考光信号是一路传播方向和六波混频信号稍有区别的双光于非简并四波混频信号.五阶非线性响应则由享生 关键词： 外差法 吸收 色散 非线性极化

Three-photon absorption and dispersion of sub-femtosecond polarization beast in reverse V-type four-level

We investigate theoretieally the color-locked twin noisy field_correlation effects in fifth_order nonlinear absorption and dispersion of ultrafast polarization beats in the RV type system.We demonstrate a phase_sensitive method for studying the three_photon six_wave mixing due to atomic coherence in this multi_level system.In the limit of the narrowband and tail approximation,the fifth_order nonlinear coefficients are independent of the color_locked noisy lights.In broadband FWM and SWM signals show time asymmetry due to field_correlation,and RDO effect of frequency_time domain.Moreover,the polarization presents RDO oscillation in frequency_domain.The reference signal is a two_photon non_degenerate four_wave mixing signal,which propagates in the direction a little different from the optical path of the SWM signal.This method is used for studying the phase dispersion of the fifth_order dispersion and absorption and for the optical heterodyne detection of the three_photon SWM signal.The fifth_order nonlinear response can be controlled and modified through the color_locked correlation of twin noisy fields.The method of phase sensitive detection can be used to detect the nonlinear absorption and dispersion of the three_photon SWM.