Abstract-Properties of BIBO crystal in the terahertz regime

Nazar Nikolaev,  Zhiming Huang,  Jingguo Huang,  Yang Li,  Yury Andreev, Grigory Lanskii

https://www.spiedigitallibrary.org/conference-proceedings-of-spie/11348/1134818/Properties-of-BIBO-crystal-in-the-terahertz-regime-Conference-Presentation/10.1117/12.2555663.full?SSO=1

In recent years, the terahertz sources have attracted much attention for its special use compared with so for UV-visible range. Crystal with high quality and special properties is their indispensable part. Optical properties such as the absorption coefficient and refractive index at three basic crystal orientations (x, y, and z-direction) of the BIBO crystal have been studied by the Terahertz Time-Domain Spectroscopy at room temperature. A large birefringence was observed. The measured refractive index components were approximated in the form of Sellmeier equations. Phase-matching curves for collinear down-conversion of IR laser frequencies into the THz domain were preliminarily estimated. A prospect of BIBO crystals as THz generators are discussed, and comparison with popular crystals is given.

Abstract-High efficient terahertz generation from cryogenic gallium phosphide based on collinear difference frequency

Jingguo Huang, Yang Li, Yanqing Gao, Gaofang Li, Zhiming Huang, Junhao Chu, Yury Andreev

https://www.spiedigitallibrary.org/conference-proceedings-of-spie/11046/1104631/High-efficient-terahertz-generation-from-cryogenic-gallium-phosphide-based-on/10.1117/12.2524100.short?SSO=1

In this paper, a high efficient terahertz source based on n-type gallium phosphide crystal via cryogenic process is investigated through collinear difference frequency generation pumper by 1064 nm Nd:YAG laser and its OPO system. Absorption coefficient of this crystal at THz range shows a dramatic decrease from ~ 50 cm^-1 to 0.5 cm-^-1 as the temperature decreases from 300 k to 80 k. Four times enhancement of the terahertz emission power and much more broad spectra range (~ 0.2- 3.8 THz) has been achieved in this kind of 0.5 mm length gallium phosphide crystal during the whole varied temperature difference frequency generation from 300 k to 80 k. These results indicate that cooling down the crystal temperature is an effective way to improve the terahertz source property, such as terahertz output power and frequency range.

© (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Abstract-Terahertz communication windows and their point-to-point transmission verification

Zhenyang Xiao, Qiujie Yang, Jingguo Huang, Zhiming Huang, Wei Zhou, Yanqing Gao, Rong Shu, and Zhiping He

https://www.osapublishing.org/ao/abstract.cfm?uri=ao-57-27-7673

Terahertz communication is recognized as a transformational technology that can meet the future demands of point-to-point communication. The study of terahertz atmospheric transmission characteristics is important for guiding the terahertz communication window selection process. In this report, based on the modified ITU-R P.676-10 model, we determined that the terahertz communication windows above 100 GHz were located at the bands at approximately 140, 220, 340, 410, and 460 GHz, which is verified by recent experiments. We also verified the feasibility of indoor point-to-point communication by the 110 m transmission experiment through the communication window around 460 GHz.

© 2018 Optical Society of America

Abstract-Terahertz Detection: Extreme Sensitivity of Room-Temperature Photoelectric Effect for Terahertz Detection

http://onlinelibrary.wiley.com/doi/10.1002/adma.201670005/full

Terahertz (THz) is the gap between infrared and microwave frequencies. THz detection is still a formidable challenge even though no suitable theory has been built until now, although considerable mechanisms have been proposed. On page 112, Z. Huang and co-workers propose a unique theory to realize an excellent photoelectric effect and experimentally demonstrate its extreme sensitivity to room-temperature THz detection.

Abstract-Extreme Sensitivity of Room-Temperature Photoelectric Effect for Terahertz Detection

http://onlinelibrary.wiley.com/doi/10.1002/adma.201503350/full

Extreme sensitivity of room-temperature photoelectric effect for terahertz (THz) detection is demonstrated by generating extra carriers in an electromagnetic induced well located at the semiconductor using a wrapped metal–semiconductor–metal configuration. The excellent performance achieved with THz detectors shows great potential to open avenues for THz detection.