摘要
以周期性极化GaAs为例,通过对3波耦合方程的分析,计算GaAs的有效非线性系数与2阶非线性系数比值、极化周期、品质因子及太赫兹功率.研究结果显示:在GaAs微腔中,有效非线性系数比值在0~1变化,最大有效非线性系数比值趋近于1,极化周期长而变化范围小,品质因子高(高Q值),存储能量大.随着有效非线性系数、较小范围内的极化周期以及品质因子的增大,太赫兹功率(强度)、效率随之显著增大.腔相位匹配补偿级联差频的失配,基于10阶级联差频GaAs微腔产生峰值功率0.267 4 MW,增大3.96倍,进一步说明基于级联差频GaAs微腔有助于产生太赫兹辐射、吸收是太赫兹源的主要影响因素之一.比较研究基于级联差频GaAs微腔与准相位匹配级联差频,前者具有更好输出特性,研究结果对基于级联差频GaAs微腔产生太赫兹具有参考价值.
The characteristics of cascaded difference-frequency generation(DFG)using a cavity phase-matched(CPM)GaAs,such as the ratio of effective nonlinear coefficient to second-order nonlinear coefficient,the polarization period,the quality factor and THz power,is calculated from the couple wave equations.The results show that the ratio of effective nonlinear coefficient to second-order nonlinear coefficient change from 0 to 1,the maximal ratio of effective nonlinear coefficient to second-order nonlinear coefficient becomes 1 in a cavity phase-matched GaAs.The polarization period is long and the range of GaAs crystal is small.The quality factor and the energy stored in the cavity are high.THz power(THz intensity)and the conversion efficiency significantly increase with the effective nonlinear coefficient,the polarization period within small range,and the quality factor.The flake optical micro-cavity to be utilized to compensate the phase mismatch,the peak power in CPM cascaded DFG processes up to 0.267 4 MW in 10-order cascading processes,THz power increases to 3.96 times,which further proves that the cascaded DFG using a CPM GaAs process contributes to efficient THz-radiation generation.Absorption is one of the main factors in the terahertz source.Comparing to cascaded DFG processes based on quasi phase-matched(QPM),cascaded DFG using a CPM GaAs has better output characteristic.The research has reference value for cascaded DFG using a CPM GaAs in the terahertz technology.
作者
黄俊滔
饶志明
谢芳森
HUANG Juntao;RAO Zhiming;XIE Fangsen(College of Physics and Communication Electronics,Jiangxi Normal University,Nanchang Jiangxi 330022,China)
出处
《江西师范大学学报（自然科学版）》
CAS
北大核心
2019年第5期478-483,共6页
Journal of Jiangxi Normal University(Natural Science Edition)
基金
国家自然科学基金(11664017)
江西省自然科学基金(20161BAB202052)
江西省教育厅科技课题(GJJ160305)资助项目
关键词
级联过程
差频
太赫兹
GAAS
腔相位匹配
太赫兹功率
cascaded process
difference-frequency
terahertz
GaAs
cavity phase-matched
terahertz power
作者简介
通信作者:谢芳森(1961-),男,江西兴国人,教授,主要从事电子信息技术与光电信息监测的研究.E-mail:xiefangsen@163.com。
