飞秒激光与铁电晶体铌酸锂作用可以激发出太赫兹波段的声子极化激元。当铌酸锂的厚度减小至亚波长量级时,晶片就成为一个将太赫兹波产生、传输、调控、探测、与物质或微结构相互作用等过程集于一体的集成化芯片,为太赫兹波的研究和应用提供了平台。同时,利用时空超分辨成像技术可以对芯片中太赫兹波的传输以及与微结构作用过程进行可视化和定量分析。回顾了一些基于铌酸锂芯片的工作,比如太赫兹波传输特性的研究、频率可调谐太赫兹波源的产生、微结构对太赫兹波的调控等,这些工作说明亚波长铌酸锂芯片是一个很有前途的太赫兹集成器件。

Terahertz phonon polaritons can be generated in ferroelectric crystal LiNbO₃ using femtosecond laser pulses. When the crystal thickness becomes comparable with or less than the terahertz wavelength, LiNbO₃ functions as an integrated chip that integrates the processes of generation, propagation, control, and detection of terahertz wave and its interaction with materials or microstructures. This provides a platform for the research and applications of terahertz waves. Moreover, by using the spatio-temporal super-resolution imaging technology, the transmission in the chip and interaction of terahertz waves with microstructures can be visualized and quantitatively analyzed. This paper reviews some works on the LiNbO₃ chip, such as the research on terahertz propagation characteristics, generation of frequency-tunable terahertz sources, and terahertz modulation using microstructures. These results demonstrate that the subwavelength LiNbO₃ chip is a promising terahertz integrated device.