A real-time imaging system based on a compact terahertz laser is constructed by employing one off-axis parabolic mirror and one silicon lens.Terahertz imaging of water,water stains,leaf veins,human hairs,and metal wir...A real-time imaging system based on a compact terahertz laser is constructed by employing one off-axis parabolic mirror and one silicon lens.Terahertz imaging of water,water stains,leaf veins,human hairs,and metal wire is demonstrated.An imaging resolution of 68μm is achieved.The experiments show that this compact and simplified imaging system is suitable for penetration demonstration of terahertz light,water distribution measurement,and imaging analysis of thin samples.展开更多
In this paper,we presented single mode terahertz quantum cascade lasers(THz QCLs)with sampled lateral grating emitting approximately 3.4 THz.Due to strong mode selection,the implementation of sampled lateral grating o...In this paper,we presented single mode terahertz quantum cascade lasers(THz QCLs)with sampled lateral grating emitting approximately 3.4 THz.Due to strong mode selection,the implementation of sampled lateral grating on THz QCL ridges can result in stable single longitudinal mode emission with a side-mode suppression ratio larger than 20 dB.The measured peak power of the grating laser is improved by about 11.8%compared to the power of devices with uniform distributed feedback gratings.Furthermore,the far-field pattern of the presented device is uninfluenced by grating structures.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61927813,61975225,and 62035014)Science and Technology Commission of Shanghai Municipality(Nos.21DZ1101102 and 21ZR1474600)。
文摘A real-time imaging system based on a compact terahertz laser is constructed by employing one off-axis parabolic mirror and one silicon lens.Terahertz imaging of water,water stains,leaf veins,human hairs,and metal wire is demonstrated.An imaging resolution of 68μm is achieved.The experiments show that this compact and simplified imaging system is suitable for penetration demonstration of terahertz light,water distribution measurement,and imaging analysis of thin samples.
基金This work was supported by the National Key R&D Program of China(No.2018YFB1801502)the National Natural Science Foundation of China(Grant Nos.61927813,61975225,and 61704181)+1 种基金the Natural Science Foundation of Shanghai(No.17ZR1448300)Shanghai International Cooperation Project(No.18590780100).
文摘In this paper,we presented single mode terahertz quantum cascade lasers(THz QCLs)with sampled lateral grating emitting approximately 3.4 THz.Due to strong mode selection,the implementation of sampled lateral grating on THz QCL ridges can result in stable single longitudinal mode emission with a side-mode suppression ratio larger than 20 dB.The measured peak power of the grating laser is improved by about 11.8%compared to the power of devices with uniform distributed feedback gratings.Furthermore,the far-field pattern of the presented device is uninfluenced by grating structures.
