摘要
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噪声场色锁互关联效应的控制改变.相位敏感方法可用于对三光子六波混频信号的光学外差探测以及研究五阶非线性极化率的吸收和色散特性.
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.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2008年第1期243-251,共9页
Acta Physica Sinica
基金
国家自然科学基金(批准号:60308002,60678005)
全国博士学位论文作者专项资金(批准号:200339)
教育部科学技术研究重点项目(批准号:105156)
霍英东教育基金会高等院校青年教师基金(批准号:101061)
高等学校博士学科点专项科研基金(批准号:20050698017)资助的课题~~
关键词
外差法
吸收
色散
非线性极化
heterodyne, absorption, dispersion, susceptibility
