We successfully demonstrate 32-Gbaud Probabilistically Shaped 4096-ary Quadrature Amplitude Modulation(PS-4096QAM)TeraHertz(THz)signal wired transmission at 325 GHz over the 1-m Hollow-Core Fiber(HCF)in a photon-assis...We successfully demonstrate 32-Gbaud Probabilistically Shaped 4096-ary Quadrature Amplitude Modulation(PS-4096QAM)TeraHertz(THz)signal wired transmission at 325 GHz over the 1-m Hollow-Core Fiber(HCF)in a photon-assisted THz-wave communication system.By employing advanced Digital Signal Processing(DSP)and the PS technique,the 352-Gbit/s line rate(288-Gbit/s net rate)delivery with a net Spectral Efficiency(SE)of 9 bit/s/Hz is realized in the experiment,satisfying the 0.86-Normalized Generalized Mutual Information(NGMI)Low-Density Parity-Check(LDPC)threshold.展开更多
This paper investigates the performances of terahertz-wave parametric oscillators (TPOs) based on the LiNbO3 crystal at different pump wavelengths.The calculated results show that TPO characteristics,including the f...This paper investigates the performances of terahertz-wave parametric oscillators (TPOs) based on the LiNbO3 crystal at different pump wavelengths.The calculated results show that TPO characteristics,including the frequency tuning range,the THz-wave gain and the stability of THz-wave output direction based on the Si-prism coupler,can be significantly improved by using a short-wavelength pump.It also demonstrates that a long-wavelength-pump allows the employment of a short TPO cavity due to an enlarged phase-matching angle,that is,an increased angular separation between the pump and oscillated Stokes beams under the THz-wave generation at a specific frequency. The study provides an useful guide and a theoretical basis for the further improvement of TPO systems.展开更多
Active terahertz-wave imaging systems play a significant role in security and surveillance applications.A 0.14 THz near-field imaging system is described,which consists of a signal generator and acquisition unit,a tra...Active terahertz-wave imaging systems play a significant role in security and surveillance applications.A 0.14 THz near-field imaging system is described,which consists of a signal generator and acquisition unit,a transceiver front end,a digital signal process unit and a motor control unit.Based on the two-dimensional synthetic aperture technique and the image reconstruction algorithm,this system is capable of producing three-dimensional images of 2 mm lateral resolution and 3 cm range resolution in concealed weapon detection experiments.展开更多
An efficient widely tunable terahertz(THz)-wave parametric oscillator (TPO) has been designed based on the basic principle of optical parametric oscillator. The design of TPO comprises the theoretical calculations...An efficient widely tunable terahertz(THz)-wave parametric oscillator (TPO) has been designed based on the basic principle of optical parametric oscillator. The design of TPO comprises the theoretical calculations for wavelength dependent refractive index dependent wavelength when the frequency is in the far infrared region, the low-loss parametric gain has been discussed as a same form as the parametric gain in the optical region, realized the non-collinear phase-matching conditions of the terahertz optical parametric oscillator and structure of lithium niobate (LiNbO3) for TPO. The tunable spectrum range of terahertz-wave has been achieved. To increase THz output, a cut exit was made at the comer of the LiNbO3 crystal.展开更多
基金supported by National Key R&D Program of China(2018YFB1800900)National Natural Science Foundation of China(61935005,91938202,61720106015,61835002,61805043,62127802).
文摘We successfully demonstrate 32-Gbaud Probabilistically Shaped 4096-ary Quadrature Amplitude Modulation(PS-4096QAM)TeraHertz(THz)signal wired transmission at 325 GHz over the 1-m Hollow-Core Fiber(HCF)in a photon-assisted THz-wave communication system.By employing advanced Digital Signal Processing(DSP)and the PS technique,the 352-Gbit/s line rate(288-Gbit/s net rate)delivery with a net Spectral Efficiency(SE)of 9 bit/s/Hz is realized in the experiment,satisfying the 0.86-Normalized Generalized Mutual Information(NGMI)Low-Density Parity-Check(LDPC)threshold.
基金Project supported in part by the Foundation for Innovative Research of Wuhan National Laboratory for Optoelectronicsthe National Basic Research Program of China (Grant No 2007CB310403)
文摘This paper investigates the performances of terahertz-wave parametric oscillators (TPOs) based on the LiNbO3 crystal at different pump wavelengths.The calculated results show that TPO characteristics,including the frequency tuning range,the THz-wave gain and the stability of THz-wave output direction based on the Si-prism coupler,can be significantly improved by using a short-wavelength pump.It also demonstrates that a long-wavelength-pump allows the employment of a short TPO cavity due to an enlarged phase-matching angle,that is,an increased angular separation between the pump and oscillated Stokes beams under the THz-wave generation at a specific frequency. The study provides an useful guide and a theoretical basis for the further improvement of TPO systems.
基金Supported by National Natural Science Foundation of China(61377019)the Natural Science Foundation of Jiangsu Province(BK20151512)+1 种基金the Government Scholarship of Jiangsu Province.Funding from Priority Academic Program Development of Jiangsu Higher Education Institutions(YX03001)Synergistic Innovation Center for Organic Electronics and Information Displays are Gratefully Acknowledged.Partial Funding From the National Laboratory of Solid State Microstructure(M27004)
文摘Active terahertz-wave imaging systems play a significant role in security and surveillance applications.A 0.14 THz near-field imaging system is described,which consists of a signal generator and acquisition unit,a transceiver front end,a digital signal process unit and a motor control unit.Based on the two-dimensional synthetic aperture technique and the image reconstruction algorithm,this system is capable of producing three-dimensional images of 2 mm lateral resolution and 3 cm range resolution in concealed weapon detection experiments.
文摘An efficient widely tunable terahertz(THz)-wave parametric oscillator (TPO) has been designed based on the basic principle of optical parametric oscillator. The design of TPO comprises the theoretical calculations for wavelength dependent refractive index dependent wavelength when the frequency is in the far infrared region, the low-loss parametric gain has been discussed as a same form as the parametric gain in the optical region, realized the non-collinear phase-matching conditions of the terahertz optical parametric oscillator and structure of lithium niobate (LiNbO3) for TPO. The tunable spectrum range of terahertz-wave has been achieved. To increase THz output, a cut exit was made at the comer of the LiNbO3 crystal.