第 44 卷 第 8 期
2011 年 8 月
天 津 大 学 学 报
Journal of Tianjin University
Vol.44 No.8
Aug.
2011
收稿日期:2010-03-11;修回日期:2010-04-06.
基金项目:国家自然科学基金资助项目(10604033);天津市自然科学基金资助项目(09JCYBJC5100).
作者简介:王
喆
(1979— ),男,博士,讲师,snowleoperd@126.com.
通讯作者:吴 强,wuqiang@nankai.edu.cn.
▋
光子晶格中超短脉冲光的时域特性
王
喆
1,2,3
,唐柏权
1,3
,杨程亮
1,3
,金妮娜
1,3
,陈 楠
1,3
,吴 强
1,3
(1. 南开大学物理科学学院光子学中心,天津 300071;
2. 天津理工大学理学院,天津 300384;
3. 南开大学泰达应用物理学院弱光非线性光子学教育部重点实验室,天津 300457)
摘 要:为定量分析光子晶格对超短脉冲的时域、频域和非线性动力学过程的操控作用,利用搭建的二次谐波型频
率分辨光学开关探测系统对超短脉冲离散衍射的出射光进行了时频域的定量探测和分析.运用广义主元素投影算法
从采集的频率分辨光学开关(FROG)迹线中定量恢复了时域电场、频域光谱以及它们的相位信息.通过对上述结果
的数值拟合,获得了脉宽、谱宽、中心波长和各阶啁啾量,并结合上述结果分析了非线性相移与色散啁啾对光谱的
影响和色散与自相位调制(SPM)对脉宽的影响.结果表明,光子晶格不但对入射光存在空间调控,同时也对脉冲光
的时域、频域以及非线性过程有着全面、灵活的调控能力;传输中,脉冲光的脉宽和频谱之间的关系受传播系统的
色散、非线性系数以及结构等诸多因素的共同制约.
关键词:飞秒脉冲;光子晶格;离散衍射;频率分辨光学开关
中图分类号:O437.5 文献标志码:A 文章编号:0493-2137(2011)08-0747-06
Temporal Properties of Ultrashort Laser Pulses in
Photonic Lattice by SHG-FROG Technique
WANG Zhe
1,2,3
,TANG Bai-quan
1,3
,YANG Cheng-liang
1,3
,JIN Ni-na
1,3
,CHEN Nan
1,3
,
WU Qiang
1,3
(1. Photonics Center,School of Physics,Nankai University,Tianjin 300071,China;
2. School of Science,Tianjin University of Technology,Tianjin 300384,China;
3. The Key Laboratory of
Weak Light Nonlinear Photonics,Ministry of Education,TEDA Applied Physics School,
Nankai University,Tianjin 300457,China)
Abstract:
A second harmonic generation frequency-resolved optical gating(SHG-FROG)detection system was buil
for quantitatively analyzing the controlling of photonic lattice for ultrashort laser pulses in temporal and frequenc
domain and its nonlinear dynamic progress. The electric field in time domain,spectrum,and their phases were quan-
titatively retrieved by the principal component generalized projection algorithm(PCGPA)from the FROG traces. The
pulse duration,bandwidth,center wavelength,and the chirp of first 5 orders were obtained by numerical fitting,
based on which,the influence of nonlinear phase shift and chirp on spectrum and the influence of dispersion and self-
phase modulation(SPM)on duration were discussed. Results show that photonic lattice can control not only an electric
magnetic wave spatially but also its properties in temporal and frequency domain and nonlinear dynamic progress
flexibly. In the propagation process,the relationship between duration and spectrum is governed by dispersion,
nonlinear coefficient,structure,and some other factors of the propagating system.
Keywords:
femtosecond pulses;photonic lattice;discrete diffraction;frequency-resolved optical gating
离散衍射(discrete diffraction)是实现离散光学孤
子(discrete optical solitons)的先决条件之一,在现代
光子学和光信息领域具有重要的学术和实用价值
[1-3]
.
离散衍射的基本途径是将光引入到光子晶格(photonic