关键词: 拉曼效应/
载波包络相位/
色散波/
时间转换法
English Abstract
Propagation of electric field of the few-cycle femtosecond pulse in nonlinear Kerr medium
Liu Dan,Hong Wei-Yi,
Guo Qi
1.Laboratory of Nanophotonic Functional Materials and Devices, South China Normal University, Guangzhou 510006, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 11274125, 11474109).Received Date:01 May 2015
Accepted Date:31 August 2015
Published Online:05 January 2016
Abstract:In this paper, the propagation of a few-cycle femtosecond pulse in a nonlinear Kerr medium is studied by the method of time-transformation. The time-transformation approach can greatly improve the computational efficiency. Because the width of electric field of the few-cycle femtosecond pulse is less than the characteristic time of Raman response in a nonlinear medium, it is observed that the electric field of the pulse experiences a significant deformation and breaks into a Raman soliton and the dispersion waves during the propagation, which can be attributed to strongly nonlocal nonlinearity. A deeper investigation of the time-frequency distributions for both the Raman soliton and the dispersion waves is also included. Since the pulse contains only few cycles, the carrier-envelope phase (CEP) of the pulse plays an important role in the process of nonlinear propagation. The numerical results show the CEP-dependence in the process of nonlinear propagation: the phase changes for both the Raman soliton and the dispersive waves are just equal to the CEP change of the initial pulse, which indicates that the CEP of the pulse is linearly transmitted in the process of nonlinear propagation. This phenomenon can be attributed to the fact that the phase change due to the nonlinearity is only dependent on the intensities of the fields of both the Raman soliton and the dispersion wave, which are unchanged for all the CEPs.
Keywords: Raman effect/
carrier-envelope phase/
dispersion-wave/
time-transformation approach
