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电子技术（上海） 2024年第5期53卷 392-393页

作者：王可嘉江苏省常州市武进区前黄实验学校江苏214000

阐述基于智能技术的实践教育模式,设计符合新课标要求的教学目标、教材选取、教学方法和评估方式。通过评估教学效果、收集学生反馈、总结经验,展望发展趋势。

关键词：智能教育教学模式教学实践

Proposal for CEP measurement based on terahertz air photonics

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Frontiers of Optoelectronics 2018年第4期11卷 407-412页

作者： kejia wang Xinyang GU Jinsong LIU Zhengang YANG Shenglie wang Wuhan National Laboratory for Optoelectronics School of Optical and Electronic information Huazhong University of Science and TechnologyWuhan 430074China

Single-shot carrier envelope phase (CEP) measurement is a challenge in the research field of ultrafast optics. We theoretically investigate how an intense terahertz pulse modulates second harmonic emission (SH) from a gas plasma induced by a few-cycle laser pulse (FCL). Results show that the modulation quantity of SH intensity has a cosinoidal dependence on the CEP of FCL pulses, based on which we propose a low energy, all-optical method for single-shot CEP measurements via using a known intense terahertz pulse. Moreover, we propose an experimental realization.

关键词： ultrafast measurements far-infrared or terahertz ultrafast nonlinear optics harmonic generation and mixing

A direct method to calculate second-order two-dimensional terahertz spectroscopy in frequency-domain based on classical theory

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Frontiers of Optoelectronics 2018年第4期11卷 413-418页

作者： Feidi XIANG kejia wang Zhengang YANG Jinsong LIU Shenglie wang Wuhan National Laboratory for Optoelectronics School of Optical and Electronic informationHuazhong University of Science and Technology Wuhan 430074China

Previous theoretical researches on the two-dimensional terahertz spectroscopy (2DTS), which are conducted via inefficiently time-consuming numerical simulation, deal with only single-mode system. To overcome the limitations, we derive a classical-theory-based analytical solution which is applicable to multi-modes system. Three typical weak sources of nonlinearities are introduced. The findings suggest that the analytical results correspond well with those obtained by the traditional numerical simulation. Thus the study provides a more efficient and practical method to directly calculate 2DTS, and, in a broader sense, sheds new light on the theory of 2DTS.

关键词： two-dimensional spectroscopy terahertz classical method

Numerical study of threshold gain behavior for a THz random laser in a two-dimensional active disordered medium with a three-level atomic system

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Chinese Science Bulletin 2011年第25期56卷 2664-2667页

作者： LIU Yong LIU JinSong wang kejia Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Tech-nology Wuhan 430074 China

By numerically solving Maxwell's equations and rate equations in a two-dimensional (2D) active random media made of ruby grains with a three-level atomic system, the threshold gain behavior for a THz random laser is investigated. The spectral intensity variation with the pumping rate is calculated for both the transverse magnetic (TM) field and the transverse electric (TE) field. The computed results show that THz random lasing could occur in a 2D disordered medium for both the TM and TE cases. Further analysis reveals that the THz lasing threshold for TM fields is lower than that for TE fields.

关键词：三能级原子系统激光阈值无序介质随机介质太赫兹数值研究行为增益

Excitation of localized modes and mechanism of random lasing forming in random media

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Chinese Science Bulletin 2006年第18期51卷 2178-2182页

作者： wang Hong LIU Jinsong wang kejia HAN Yanling State Key Laboratory of Laser Technology Huazhong University of Science and Teelmology Wuhan 430074 China

Laser phenomena in random media have been studied based on the localized theory for lightwave in random media. The relationship between random lasing modes and localized modes has been investigated by directly solving Maxwell equations numerically via the finite difference time domain method. The spatial distribution and the spectra of localized modes are obtained for both passive and active random media. The results show that random lasing modes directly originate from the localized modes inside the random medium. In the presence of gain, any one of the localized modes can be amplified and can serve as random lasing mode.

关键词：激光物理学光学性能激光作用随机媒质

Microwave transmission properties of metamaterials with double sets of square holes

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Chinese Science Bulletin 2012年第28期57卷 3769-3772页

作者： ZOU Si LIU JinSong wang kejia Wuhan National Laboratory for Optoelectronics School of Optoelectronie Science and Engineering Huazhong University of Science andTechnology Wuhan 430074 China

The transmission property of microwave through a kind of metamaterial is investigated *** metamaterials are fabricated with a structure of double sets of square holes:subwavelength ones,and small ones whose sizes and spacing are smaller at least one order of magnitude than those of the subwavelength *** experimental results show that the peak power of the measured transmission spectra is dependent on the structure parameters of the small *** physical origin to create this phenomenon is that the designer surface plasmons sustained by the small holes affect on the transmission property of the microwave passing through the subwavelength *** results are promising for proposing some techniques for optoelectronic devices in terahertz and microwave regime.

关键词：传输特性微波方孔材料表面等离激元结构参数光电子器件峰值功率

Polarization-dependent difference of the power spectra from two-dimensional random media with different shapes

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Chinese Science Bulletin 2009年第18期54卷 3215-3219页

作者： LIU Hai LIU JinSong LU JianTao wang kejia Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Sci-ence and Technology Wuhan 430074 China School of Information and Electrical Engineering China University of Mining and Technology Xuzhou 221116 China

Polarization-dependent difference of the power spectra from a set of two-dimensional (2D) passive random media is investigated by simultaneously solving Maxwell’s equations for both transverse magnetic (TM) and transverse electric (TE) fields. The random media have the same random constitution but different shapes. Results show that both two polarized states are morphology dependent, and the variety of the shapes has more influence on the selection of TM polarized modes than that of TE polarized modes. Such polarization-dependent difference of morphology property presents a new modeselecting technique for random lasers.

关键词：随机介质功率谱形状二维偏振依赖性麦克斯韦方程组极化状态

Influence of the amplitude ratio between two terahertz pulses on two-dimensional spectroscopy

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Chinese Science Bulletin 2014年第2期59卷 138-146页

作者： Jiangsheng Hu Jinsong Liu Huquan Li kejia wang Zhengang Yang Shenglie wang Wuhan National Laboratory for Optoelectronics School of Optical and Electronic Information Huazhong University of Science and Technology

The influence of the amplitude ratio between the two THz pulses on two-dimension THz spectroscopy(2DTS)has been studied theoretically via a classical method in which the expressions for the second-order nonlinearity were derived using perturbation approach,and the THz pulses were not treated as a delta *** types of nonlinear sources i.e.,anharmonicity,nonlinear damping,and nonlinear coupling,are considered in a single mode *** simulation results demonstrated that the amplitude ratio had a notable influence on the 2DTSs,and different sources have different *** study is promising for guiding future experiments.

关键词：太赫兹脉冲振幅比二维谱线性表达式非线性耦合非线性阻尼经典方法非线性源

Time behavior of field screening effects in small-size GaAs photoconductive terahertz antenna

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Frontiers of Optoelectronics 2015年第1期8卷 98-103页

作者： Tianyi wang Zhengang YANG Si ZOU kejia wang Shenglie wang Jinsong LIU Wuhan National Laboratory for Optoelectronics School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan 430074 China

The field screening effects in small-size GaAs photoconductive （PC） antenna are investigated via the well-known pump and probe terahertz （THz） generation technique. The peak amplitude of the THz pulses excited by the probe laser pulse as a function of the pump-probe time delay was measured. An equivalent-circuit model was used to simulate the experimental data. Based on the good agreement between the results of simulation and experiment, the time behavior of the radiation and space-charge fields was simulated. The results show that the spacecharge screening dominantly determines the device response in the whole time, while the radiation filed screening plays a key role in initial time which strongly affects the peak THz field. The parameter analysis was performed, which may be valuable on the optimum design for the antenna as a THz emitter.

关键词： GaAs photoconductive (PC) antenna field screening effects terahertz (THz) emitter

Oscillation effect in frequency domain current from a photoconductive antenna via double-probe-pulse terahertz detection technique

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Frontiers of Optoelectronics 2015年第1期8卷 104-109页

作者： Qi JIN Jinsong LIU kejia wang Zhengang YANG Shenglie wang Kefei YE Wuhan National Laboratory for Optoelectronics School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan 430074 China

Via constructing a special terahertz time domain spectroscopy （THz-TDS） system in which two femtosecond （fs） laser pulses were used as probe pulses to excite a photoconductive （PC） THz detector, the time behavior of the current from the detector was *** corresponding theoretical analysis was performed by a well-known equivalent-circuit model. When the time domain current was transformed to frequency domain, an oscillation effect was observed. The oscillation frequency was decided by the time delay between the two probe pulses. The number of the extrema in the frequency domain current curve was proportion to the pulse interval in 0.1 -2 THz. A method to measure the interval offs laser pulses was proposed. It is important for applications of fs laser pulses or train.

关键词： terahertz (THz) photoconductivity frequency oscillation