In this work, we review the developing progress of two-dimensional terahertz time-domain spectroscopy（THz-TDS） and its diverse applications, including analyzing the polarization of THz radiation from a laser-induced...In this work, we review the developing progress of two-dimensional terahertz time-domain spectroscopy（THz-TDS） and its diverse applications, including analyzing the polarization of THz radiation from a laser-induced plasma source and studying the corresponding physical mechanism, and characterizing the optical properties of crystals, etc.展开更多
The optimization of the fiber-coupled terahertz time-domain spectroscopy（THz-TDS） system is performed by changing the polarization of the optical excitation pulse centered at 1550 nm. In Ga As/In Al As multilayer st...The optimization of the fiber-coupled terahertz time-domain spectroscopy（THz-TDS） system is performed by changing the polarization of the optical excitation pulse centered at 1550 nm. In Ga As/In Al As multilayer structures based photoconductive antennas are used in TDS setup as both the emitter and receiver. The experimental results demonstrate that not only the THz signal power but also the temporal waveform vary with the rotation of the exciting pulse polarization. Maximum output power of the emitter is obtained when the polarization of the pump pulse is perpendicular to the edge of the metal electrodes. At this moment the THz waveform is close to a single-cycled pulse. However, double THz pulses could be recorded when the pump laser polarization is parallel to the electrodes. Laser pulse splitting induced by the birefringence of the optical fiber may attribute to the polarizationdependent performance of the fiber-coupled THz-TDS system.展开更多
We give a brief review of the developments in terahertz time-domain spectroscopy(THz-TDS) systems and microcavity components for probing samples in the University of Shanghai for Science and Technology. The broadband ...We give a brief review of the developments in terahertz time-domain spectroscopy(THz-TDS) systems and microcavity components for probing samples in the University of Shanghai for Science and Technology. The broadband terahertz(THz) radiation sources based on GaAs m-i-n diodes have been investigated by applying high electric fields. Then, the free space THz-TDS and fiber-coupled THz-TDS systems produced in our lab and their applications in drug/cancer detection are introduced in detail. To further improve the signal-to-noise ratio(SNR) and enhance sensitivity, we introduce three general micro-cavity approaches to achieve tiny-volume sample detection, summarizing our previous results about their characteristics, performance, and potential applications.展开更多
基金supported by the National Basic Research Program of China under Grant No.2014CB339802,No.2011CB808100the National Natural Science Foundation of China under Grant No.11174156
文摘In this work, we review the developing progress of two-dimensional terahertz time-domain spectroscopy（THz-TDS） and its diverse applications, including analyzing the polarization of THz radiation from a laser-induced plasma source and studying the corresponding physical mechanism, and characterizing the optical properties of crystals, etc.
基金supported by National Basic Research Program of China under Grant No.2014CB339802,No.2011CB808100National Natural Science Foundation of China under Grant No.11174156
文摘The optimization of the fiber-coupled terahertz time-domain spectroscopy（THz-TDS） system is performed by changing the polarization of the optical excitation pulse centered at 1550 nm. In Ga As/In Al As multilayer structures based photoconductive antennas are used in TDS setup as both the emitter and receiver. The experimental results demonstrate that not only the THz signal power but also the temporal waveform vary with the rotation of the exciting pulse polarization. Maximum output power of the emitter is obtained when the polarization of the pump pulse is perpendicular to the edge of the metal electrodes. At this moment the THz waveform is close to a single-cycled pulse. However, double THz pulses could be recorded when the pump laser polarization is parallel to the electrodes. Laser pulse splitting induced by the birefringence of the optical fiber may attribute to the polarizationdependent performance of the fiber-coupled THz-TDS system.
基金the National Key R&D Program of China (No. 2018YFF01013003)the Program of Shanghai Pujiang Program, China (No. 17PJD028)+4 种基金the National Natural Science Foundation of China (Nos. 61671302, 61601291, and 61722111)the Shuguang Program supported by the Shanghai Education Development Foundation and Shanghai Municipal Education Commission, China (No. 18SG44)the Key Scientific and Technological Project of Science and Technology Commission of Shanghai Municipality, China (No. 15DZ0500102)the Shanghai Leading Talent, China (No. 2016-019)the Young Yangtse Rive Scholar, China (No. Q2016212).
文摘We give a brief review of the developments in terahertz time-domain spectroscopy(THz-TDS) systems and microcavity components for probing samples in the University of Shanghai for Science and Technology. The broadband terahertz(THz) radiation sources based on GaAs m-i-n diodes have been investigated by applying high electric fields. Then, the free space THz-TDS and fiber-coupled THz-TDS systems produced in our lab and their applications in drug/cancer detection are introduced in detail. To further improve the signal-to-noise ratio(SNR) and enhance sensitivity, we introduce three general micro-cavity approaches to achieve tiny-volume sample detection, summarizing our previous results about their characteristics, performance, and potential applications.
