Terahertz pulses from semiconductor-air interfaces
Terahertz pulses from semiconductor-air interfaces
复制标题
来自半导体-空气界面的太赫兹脉冲
DOI：
10.1063/1.107541
复制
发表时间：
1992
影响因子：
4
通讯作者：
S. Keiding
中科院分区：
文献类型：
--
作者：
J. E. Pedersen;I. Balslev;J. Hvam;S. Keiding
我们报告了一个意想不到的观察强太赫兹脉冲，辐射垂直于半导体空气界面照射飞秒激光脉冲在正常入射。对称性的论点排除辐射发射严格沿着方向的表面电场和偶极子，垂直于界面。我们将我们的观测结果归因于由小的电介质透镜收集的辐射的强界面诱导的角度重新分布。对于检测，太赫兹衍射光斑内的小对称性破坏位移就足够了。
We report an unexpected observation of strong terahertz pulses, radiated perpendicular to semiconductor‐air interfaces illuminated by femtosecond laser pulses at normal incidence. Symmetry arguments preclude radiation emitted strictly along the direction of the surface electric field and the dipoles, normal to the interface. We attribute our observations to the strong interface‐induced angular redistribution of the radiation being collected by a small dielectric lens. For detection, a small symmetry breaking displacement within the terahertz diffraction spot is sufficient.