An Inversion Domain Superlattice of 4H-SiC for Room-Temperature and Tunable Terahertz Generation

作者：Yang, Run; Yan, Kang; Huang, Yao; Liu, Xiaoxu; Chen, Jian; Zhang, Zhiyong^*; Wu, Xinglong^*

来源：Crystal Growth & Design, 2018, 18(10): 5733-5737.

DOI：10.1021/acs.cgd.8b00890

• DIFFERENCE-FREQUENCY-GENERATION
• SILICON-CARBIDE
• THZ
• RADIATION
• TECHNOLOGY

An inversion domain superlattice of 4H-SiC is designed theoretically for generating room-temperature and tunable terahertz (THz) radiation via the combination of the density functional theory and classic coupled-wave equations. For such symmetric structures, our calculations indicate that only the Raman and infrared active E' modes contribute to the THz parametric generation in the frequency range of 0.2-3.3 THz. The lowest E' modes correspond to the relative shearing movement of the C-C and Si-Si double layers, and its energy can be adjusted to the sub-THz region by increasing length of the superlattice unit cell. With a pump source operating at 1.064 pm, the maximal THz gain in the process of stimulated polariton scattering was obtained to be 1.26 cm(-1) at room temperature for a y-plate superlattice, which is slightly lower than that in the commonly used LiNbO3 under the same pump power. Such inversion domain superlattices of 4H-SiC with different unit lengths can be prepared experimentally via the atomic layer epitaxy method.

• 出版日期2018-10
• 单位固体微结构物理国家重点实验室; 南京大学