本文提出一种采用石榴石型铁氧体磁性材料的太赫兹滤波器,利用波导线缺陷和腔内点缺陷的耦合特性,通过改变腔内介质柱半径及分布,实现对某个波长的耦合,达到了高效率滤波的功能;改变外磁场的大小,影响铁氧体材料的磁导率变化,使谐振频...本文提出一种采用石榴石型铁氧体磁性材料的太赫兹滤波器,利用波导线缺陷和腔内点缺陷的耦合特性,通过改变腔内介质柱半径及分布,实现对某个波长的耦合,达到了高效率滤波的功能;改变外磁场的大小,影响铁氧体材料的磁导率变化,使谐振频率发生改变,从而对THz波进行滤波.应用平面波展开法(PWM)和时域差分有限法(FDTD)进行仿真分析,研究结果表明,该滤波器其插入损耗为0.0997 d B,3 d B带宽为8.22 GHz,实现了低损耗窄带滤波.展开更多
The tunable terahertz（THz） filter has been designed and studied, which is composed of 1D photonic crystal（PC） containing a defect layer of semiconductor Ga As. The analytical solution of 1D defective PC（1DDPC） i...The tunable terahertz（THz） filter has been designed and studied, which is composed of 1D photonic crystal（PC） containing a defect layer of semiconductor Ga As. The analytical solution of 1D defective PC（1DDPC） is deduced based on the transfer matrix method, and the electromagnetic plane wave numerical simulation of this 1DDPC is performed by using the finite element method. The calculated and simulated results have confirmed that the filtering transmittance of this 1DDPC in symmetric structure of air/（Si/SiO_2）~N/GaAs/（SiO_2/Si）~N/air is far higher than in asymmetric structure of air/（Si/SiO_2）~N/GaAs/（Si/SiO_2）~N/air, where the filtering frequency can be tuned by the external pressure. It can provide a feasible route to design the external pressure-controlled THz filter based on 1DPC with a defective semiconductor.展开更多
We experimentally demonstrate a mechanically tunable metamaterials terahertz（THz） dual-band bandstop filter. The unit cell of the filter contains an inner aluminum circle and an outside aluminum Ohm-ring on high res...We experimentally demonstrate a mechanically tunable metamaterials terahertz（THz） dual-band bandstop filter. The unit cell of the filter contains an inner aluminum circle and an outside aluminum Ohm-ring on high resistance silicon substrate. The performance of the filter is simulated by finite-integration-time-domain（FITD） method. The sample is fabricated using a surface micromachining process and experimentally demonstrated using a THz time-domain-spectroscopy（TDS） system. The results show that, when the incident THz wave is polarized in y-axis, the filter has two intensive absorption peaks locating at 0.71 THz and 1.13 THz, respectively. The position of the high-frequency absorption peak and the amplitude of the low-frequency absorption peak can be simultaneously tuned by rotating the sample along its normal axis.The tunability of the high-frequency absorption peak is due to the shift of resonance frequency of two electrical dipoles,and that of the low-frequency absorption peak results from the effect of rotationally induced transparent. This tunable filter is very useful for switch, manipulation, and frequency selective detection of THz beam.展开更多
设计并实现了一种采用进口电火花技术加工的D波段电感膜片耦合的矩形波导空腔滤波器。采用等效电路法设计了一个140 GHz矩形空腔带通滤波器。采用有限元仿真软件HFSS分析了腔体个数对滤波器主要性能的影响,最终成功设计了一个性能优良...设计并实现了一种采用进口电火花技术加工的D波段电感膜片耦合的矩形波导空腔滤波器。采用等效电路法设计了一个140 GHz矩形空腔带通滤波器。采用有限元仿真软件HFSS分析了腔体个数对滤波器主要性能的影响,最终成功设计了一个性能优良的四阶空腔滤波器,中心频率(140±3)GHz,带内插入损耗S21在-3 d B以内,回波损耗S11在-20 d B以下。采用电火花微加工技术成功加工出了四阶滤波器的主体部分,相应完成了结构键合等关键工艺,首次制作了基于电火花技术的D波段矩形波导空腔滤波器。测试结果为中心频率(138.5±3)GHz,带内插入损耗最好达到了-4.4 d B。结果表明滤波器在140GHz具有带通特性和滤波功能,尽管与理论上的-3 d B有差异,但考虑到加工误差、夹具损耗等情况下,样品主要技术指标与设计值较为一致。展开更多
文摘本文提出一种采用石榴石型铁氧体磁性材料的太赫兹滤波器,利用波导线缺陷和腔内点缺陷的耦合特性,通过改变腔内介质柱半径及分布,实现对某个波长的耦合,达到了高效率滤波的功能;改变外磁场的大小,影响铁氧体材料的磁导率变化,使谐振频率发生改变,从而对THz波进行滤波.应用平面波展开法(PWM)和时域差分有限法(FDTD)进行仿真分析,研究结果表明,该滤波器其插入损耗为0.0997 d B,3 d B带宽为8.22 GHz,实现了低损耗窄带滤波.
基金partially supported by National Natural Science Foundation of China(Grant Nos.11174147,11175152 and11704326)the Funding of Jiangsu Innovation Program for Graduate Education(Grant No.KYLX15_0316)the Fundamental Research Funds for the Central Universities
文摘The tunable terahertz（THz） filter has been designed and studied, which is composed of 1D photonic crystal（PC） containing a defect layer of semiconductor Ga As. The analytical solution of 1D defective PC（1DDPC） is deduced based on the transfer matrix method, and the electromagnetic plane wave numerical simulation of this 1DDPC is performed by using the finite element method. The calculated and simulated results have confirmed that the filtering transmittance of this 1DDPC in symmetric structure of air/（Si/SiO_2）~N/GaAs/（SiO_2/Si）~N/air is far higher than in asymmetric structure of air/（Si/SiO_2）~N/GaAs/（Si/SiO_2）~N/air, where the filtering frequency can be tuned by the external pressure. It can provide a feasible route to design the external pressure-controlled THz filter based on 1DPC with a defective semiconductor.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61265005 and 11574059)the Natural Science Foundation of Guangxi,China(Grant Nos.2015GXNSFDA19039 and 2014GXNSFAA118376)+1 种基金the Foundation from Guangxi Key Laboratory of Automatic Detection Technology and Instrument,China(Grant Nos.YQ14114 and YQ15106)the Innovation Project of Guangxi Graduate Education,China(Grant Nos.2016YJCX03 and2016YJCX31)
文摘We experimentally demonstrate a mechanically tunable metamaterials terahertz（THz） dual-band bandstop filter. The unit cell of the filter contains an inner aluminum circle and an outside aluminum Ohm-ring on high resistance silicon substrate. The performance of the filter is simulated by finite-integration-time-domain（FITD） method. The sample is fabricated using a surface micromachining process and experimentally demonstrated using a THz time-domain-spectroscopy（TDS） system. The results show that, when the incident THz wave is polarized in y-axis, the filter has two intensive absorption peaks locating at 0.71 THz and 1.13 THz, respectively. The position of the high-frequency absorption peak and the amplitude of the low-frequency absorption peak can be simultaneously tuned by rotating the sample along its normal axis.The tunability of the high-frequency absorption peak is due to the shift of resonance frequency of two electrical dipoles,and that of the low-frequency absorption peak results from the effect of rotationally induced transparent. This tunable filter is very useful for switch, manipulation, and frequency selective detection of THz beam.
文摘设计并实现了一种采用进口电火花技术加工的D波段电感膜片耦合的矩形波导空腔滤波器。采用等效电路法设计了一个140 GHz矩形空腔带通滤波器。采用有限元仿真软件HFSS分析了腔体个数对滤波器主要性能的影响,最终成功设计了一个性能优良的四阶空腔滤波器,中心频率(140±3)GHz,带内插入损耗S21在-3 d B以内,回波损耗S11在-20 d B以下。采用电火花微加工技术成功加工出了四阶滤波器的主体部分,相应完成了结构键合等关键工艺,首次制作了基于电火花技术的D波段矩形波导空腔滤波器。测试结果为中心频率(138.5±3)GHz,带内插入损耗最好达到了-4.4 d B。结果表明滤波器在140GHz具有带通特性和滤波功能,尽管与理论上的-3 d B有差异,但考虑到加工误差、夹具损耗等情况下,样品主要技术指标与设计值较为一致。
