Abstract-High-energy terahertz wave parametric oscillator with a surface-emitted ring-cavity configuration

Zhen Yang, Yuye Wang, Degang Xu, Wentao Xu, Pan Duan, Chao Yan, Longhuang Tang, and Jianquan Yao
https://www.osapublishing.org/ol/abstract.cfm?uri=ol-41-10-2262

A surface-emitted ring-cavity terahertz (THz) wave parametric oscillator has been demonstrated for high-energy THz output and fast frequency tuning in a wide frequency range. Through the special optical design with a galvano-optical scanner and four-mirror ring-cavity structure, the maximum THz wave output energy of 12.9 μJ/pulse is achieved at 1.359 THz under the pump energy of 172.8 mJ. The fast THz frequency tuning in the range of 0.7–2.8 THz can be accessed with the step response of 600 μs. Moreover, the maximum THz wave output energy from this configuration is 3.29 times as large as that obtained from the conventional surface-emitted THz wave parametric oscillator with the same experimental conditions.

© 2016 Optical Society of America

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Abstract-Single pixel imaging with tunable terahertz parametric oscillator

Pan Duan, Yuye Wang, Degang Xu, Chao Yan, Zhen Yang, Wentao Xu, Wei Shi, and Jianquan Yao
https://www.osapublishing.org/ao/abstract.cfm?uri=ao-55-13-3670

A method of active terahertz imaging based on compressive sampling is demonstrated. A metal mask structure is designed with all modulation matrices engraved on. The imaging approach based on the mask eliminates the need for imaging object movement in point-wise scanning and shows high sensitivity. A terahertz parametric oscillator with tunability from 0.5 to 2.7 THz was used as the light source. Holes with circular, rectangular, and letter “H” shapes were imaged at 1.75 THz at 20% sampling rate. The influence of sampling rates and averaging times on the image was analyzed. Imaging of the letter “H” at different frequencies from 1.0 to 2.2 THz was tested and evaluated, and recognizable results were obtained in the range of 1.4–2.0 THz.

© 2016 Optical Society of America

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Abstract-Green laser induced terahertz tuning range expanding in KTiOPO4 terahertz parametric oscillator

Chao Yan^1,2, Yuye Wang^1,2,3,a), Degang Xu^1,2,a), Wentao Xu^1,2,Pengxiang Liu^1,2, Dexian Yan^1,2, Pan Duan^1,2, Kai Zhong^1,2, Wei Shi^1,2 and Jianquan Yao^1,2
 HIDE AFFILIATIONS
1 Institute of Laser and Optoelectronics, College of Precision Instrument and Optoelectronic Engineering, Tianjin University, Tianjin 300072, China
2 Key Laboratory of Optoelectronic Information Science and Technology (Ministry of Education), Tianjin University, Tianjin 300072, China
3 Institute of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing 400038, China
a) Authors to whom correspondence should be addressed. Electronic addresses:yuyewang@tju.edu.cn and xudegang@tju.edu.cn.
Appl. Phys. Lett. 108, 011107 (2016); http://dx.doi.org/10.1063/1.4939548
http://scitation.aip.org/content/aip/journal/apl/108/1/10.1063/1.4939548?TRACK=RSS

532 nm green laser is utilized to achieve terahertz tuning range expanding in KTiOPO4 terahertz parametric oscillator. With the theoretical analysis of the stimulated polaritonscattering, an expanded tunability of the KTiOPO4 terahertz parametric oscillator can be realized. A wide terahertz output tuning range from 5.7 to 6.1 THz, from 7.4 to 7.8 THz, from 11.5 to 11.8 THz, and from 13.3 to 13.5 THz was demonstrated in our experiment, and the result well matched the analysis. The maximum terahertz output energy was 1.61 μJ under the pump energy of 140 mJ, corresponding to the maximum THz wave conversion efficiency of 1.3 × 10⁻⁵, and the threshold pump energy is about 30 mJ.