红外与激光工程
紅外與激光工程
홍외여격광공정
INFRARED AND LASER ENGINEERING
2014年
12期
3903-3906
,共4页
吴斌%刘志明%王恒飞%应承平%王俊龙%刘红元%李国超%王洪超
吳斌%劉誌明%王恆飛%應承平%王俊龍%劉紅元%李國超%王洪超
오빈%류지명%왕항비%응승평%왕준룡%류홍원%리국초%왕홍초
相位匹配%GaAs波导%THz产生
相位匹配%GaAs波導%THz產生
상위필배%GaAs파도%THz산생
phase matching%GaAs waveguide%terahertz generation
为提高太赫兹(THz)波的产生效率，研究了飞秒激光与GaAs晶体的相互作用。首先研究了块状GaAs晶体中泵浦光与THz波间的相位匹配，结果显示泵浦光的群折射率曲线与THz波的折射率曲线不存在交点，表明了块状晶体结构中相位失配问题的存在；然后设计了四种不同尺寸的波导结构，根据波导理论计算了波导结构在0.1~6 THz波段的折射率，并结合波导的吸收和色散参数分析了THz波在晶体中的最佳传输距离。研究结果表明，GaAs波导结构能够有效增大泵浦光与THz波的相位匹配程度，从而提高飞秒激光与晶体耦合过程中THz波的产生效率。研究为基于飞秒激光与GaAs晶体相互作用的高效THz产生技术提供了理论依据。
為提高太赫玆(THz)波的產生效率，研究瞭飛秒激光與GaAs晶體的相互作用。首先研究瞭塊狀GaAs晶體中泵浦光與THz波間的相位匹配，結果顯示泵浦光的群摺射率麯線與THz波的摺射率麯線不存在交點，錶明瞭塊狀晶體結構中相位失配問題的存在；然後設計瞭四種不同呎吋的波導結構，根據波導理論計算瞭波導結構在0.1~6 THz波段的摺射率，併結閤波導的吸收和色散參數分析瞭THz波在晶體中的最佳傳輸距離。研究結果錶明，GaAs波導結構能夠有效增大泵浦光與THz波的相位匹配程度，從而提高飛秒激光與晶體耦閤過程中THz波的產生效率。研究為基于飛秒激光與GaAs晶體相互作用的高效THz產生技術提供瞭理論依據。
위제고태혁자(THz)파적산생효솔，연구료비초격광여GaAs정체적상호작용。수선연구료괴상GaAs정체중빙포광여THz파간적상위필배，결과현시빙포광적군절사솔곡선여THz파적절사솔곡선불존재교점，표명료괴상정체결구중상위실배문제적존재；연후설계료사충불동척촌적파도결구，근거파도이론계산료파도결구재0.1~6 THz파단적절사솔，병결합파도적흡수화색산삼수분석료THz파재정체중적최가전수거리。연구결과표명，GaAs파도결구능구유효증대빙포광여THz파적상위필배정도，종이제고비초격광여정체우합과정중THz파적산생효솔。연구위기우비초격광여GaAs정체상호작용적고효THz산생기술제공료이론의거。
To enhance the generation efficiency of THz wave, the interaction between femto-second laser pulse and GaAs crystal was studied. Firstly, the phase matching in bulk GaAs crystal between femto-second laser pulse and the generated terahertz wave was studied, and the result showed there was no intersection point between the refractive curve of pump laser and that of the THz wave, which indicated phase matching could not be achieved in this structure. Four waveguide structures then were proposed, and the refractive index curves in 0.1~6 THz were calculated based on related theory of waveguide, and the transmission length of the THz wave in the waveguide was also analyzed via the parameters of absorbance and dispersion. The results illustrate the phase matching is enhanced in the waveguide structures, and the generation efficiency of THz wave is supposed to get a promotion. The work serves the theory evidence for terahertz generation based on the interaction between femto-second laser and GaAs crystal.
