摘要
针对差频产生太赫兹(THz)辐射转换效率低的缺点,提出了级联差频的新机理以提高转换效率,并以ZnTe晶体为例,对级联差频产生THz辐射的原理和过程进行了理论研究.通过对级联差频耦合波方程组的求解,得出了ZnTe晶体中级联差频的最佳抽运条件和ZnTe晶体的最佳长度,并且分析了晶体吸收、波矢失配及抽运强度对级联差频的影响.计算结果表明,通过级联差频可以大大提高THz波的转换效率,其光子转换效率甚至可以超过Manley-Rowe关系的限制.
A novel mechanism of cascaded difference frequency generation （ DFG） is advanced in this article to solve the problem of low-efficiency in terahertz （THz） DFG. The cascaded DFG process is theoretically analyzed using ZnTe crystal as an example. The optimal pumping condition and crystal length is obtained,and the effects of crystal absorption,wave number mis-match and pumping intensity are investigated by solving the coupling wave equations of cascaded DFG. It is obviously seen from the calculation results that the terahertz conversion efficiency can be greatly enhanced in cascaded DFG,in which the photon conversion efficiency can even break through the Manley-Rowe limit.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2011年第3期285-292,共8页
Acta Physica Sinica
基金
国家重点基础研究发展计划(973)项目(批准号:2007CB310403)
国家自然科学基金(批准号:60801017和10874128)资助的课题~~
关键词
太赫兹辐射
差频
级联
ZnTe晶体
terahertz radiation
difference frequency generation
cascaded
ZnTe crystal
