基于DAST晶体的高能量超宽带可调谐小型化差频THz辐射源研究  

High-energy,ultra-wideband tunable and compact terahertz source based on DAST crystal via difference frequency generation

作　　者：贺奕焮 庞子博[3] 朱先立 徐德刚[1,2] 王与烨[1,2,4] 孟大磊 武聪[3] 程虹娟[3] 徐永宽 姚建铨[1,2] HE Yi-Xin;PANG Zi-Bo;ZHU Xian-Li;XU De-Gang;Wang Yu-Ye;MENG Da-Lei;WU Cong;CHENG Hong-Juan;XU Yong-Kuan;YAO Jian-Quan(Institute of Laser and Optoelectronics, School of Precision Instrument andOpto-electronics Engineering, Tianjin University, Tianjin 300072, China;Key Laboratory of Opto-electronics Information Technology (Ministry of Education), Tianjin University, Tianjin 300072, China;The 46th research institute of China Electronics Technology Group Corporation, Tianjin 300220, China;Institute of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing 400038, China)

机构地区：[1]天津大学精密仪器与光电子工程学院激光与光电子研究所,天津300072 [2]天津大学光电信息技术教育部重点实验室,天津300072 [3]中国电子科技集团公司第四十六研究所,天津300220 [4]第三军医大学西南医院神经外科,重庆400038

出　　处：《红外与毫米波学报》2019年第4期485-492,共8页Journal of Infrared and Millimeter Waves

基　　金：国家973计划(2015CB755403);国家重点研发专项(2016YFC0101001);国家自然科学基金(61775160,61771332,61471257);中国博士后科学基金(2016M602954);重庆市博士后科研项目(Xm2016021)~~

摘　　要：基于双温区法生长的高质量 DAST(4 (4 二甲基氨基苯乙烯基)甲基吡啶对甲苯酸盐)晶体成功搭建了高能量、超宽带可调谐差频THz辐射源系统尺寸40cm×25cm 调谐范围达到0.3~19.6THz 最大输出能量达到4.02μJ/pulse@18.6 THz 信噪比最高达到32.24 dB 结合振镜扫描技术以0.1 THz为步长超宽带光谱扫描时间小于1 min.实验中观测到差频产生 THz 波的输出饱和现象并研究了基于 DAST 晶体差频产生 THz 波的偏振特性与传输特性证明基于 DAST 晶体差频产生的 THz 波消光比达到 0.05 且差频过程满足 0 类相位匹配条件.基于该太赫兹辐射源对多种固体样品在 2 ~14 THz 范围内的超宽带 THz 光谱信息进行了有效获取.We have demonstrated a compact, high-energy and broadly tunable monochromatic terahertz (THz) source with the dimensional size of 40 cm×25 cm, based on difference frequency generation (DFG) in 4-N, N -dimethylamino-4′-N′-methybazoliumtoyslate (DAST) crystal, grown in two-zone growth method. The THz frequency was tuned randomly and rapidly in the range of 0.3~19.6 THz due to the widely tunable KTP-OPO and galvano-optical beam scanner. The highest pulse energy of 4.02 μJ was obtained at 18.6THz in our system. And the highest signal to noise ratio of 32.24 dB was realized at 4.3 THz using 4K-Bolometer detector. Furthermore, the characteristics of THz polarization and divergence angle were measured experimentally. Saturation phenomenon for THz output was observed and studied. Moreover, the transmission THz spectroscopies of materials in solid state were measured with the ultra-wideband tunable THz source based on DAST crystal.

关 键 词：DAST 晶体 太赫兹 超宽带可调谐 

分 类 号：O437[机械工程—光学工程]