Enhancement of terahertz electromagnetic wave emission from an undoped GaAs∕n-type GaAs epitaxial layer structure
Enhancement of terahertz electromagnetic wave emission from an undoped GaAs∕n-type GaAs epitaxial layer structure
复制标题
未掺杂GaAs∕n型GaAs外延层结构增强太赫兹电磁波发射
DOI：
--
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
M. Nakayama
中科院分区：
文献类型：
--
作者：
H. Takeuchi;J. Yanagisawa;T. Hasegawa;M. Nakayama
我们研究了未掺杂的GaAs（200nm）∕n型GaAs（3μm）外延层结构（i-GaAs∕n-GaAs结构）的太赫兹电磁波发射，其中n-GaAs层的掺杂浓度为3×1018cm−3。研究发现i-GaAs∕n-GaAs样品的太赫兹波首爆振幅明显大于n-GaAs晶体，这意味着i-GaAs层增强了太赫兹发射强度。通过将泵浦光束能量调整到较高能量侧，i-GaAs∕n-GaAs 样品的首次爆发振幅超过了被称为最强太赫兹发射器之一的 i-InAs 晶体。因此，我们得出结论，i-GaAs∕n-GaAs 结构有助于获得强太赫兹发射。
We have investigated the emission of the terahertz electromagnetic wave from an undoped GaAs (200nm)∕n-type GaAs (3μm) epitaxial layer structure (i-GaAs∕n-GaAs structure), where the doping concentration of the n-GaAs layer is 3×1018cm−3. It is found that the first-burst amplitude of terahertz wave of the i-GaAs∕n-GaAs sample is remarkably larger than that of a n-GaAs crystal, which means that the i-GaAs layer enhances the terahertz emission intensity. The first-burst amplitude of the i-GaAs∕n-GaAs sample, by tuning the pump-beam energy to the higher energy side, exceeds that of an i-InAs crystal that is known as one of the most intense terahertz emitters. We, therefore, conclude that the i-GaAs∕n-GaAs structure is useful to obtain intense terahertz emission.