The asymmetric transmission(AT) and polarization conversion of terahertz(THz) wave play a vital role in future THz communication,spectrum,and information processing.Generally,it is very difficult and complicated to ac...The asymmetric transmission(AT) and polarization conversion of terahertz(THz) wave play a vital role in future THz communication,spectrum,and information processing.Generally,it is very difficult and complicated to actively control the AT of electromagnetic(EM) wave by using traditional devices.Here,we theoretically demonstrate a stereo-metamaterial(stereo-MM) consisting of a layer of metal structure and a layer of phase transition structure with a polyimide spacer in between.The performance of the device is simulated by using the finite-integration-technology(FIT).The results show that the AT and polarization conversion of linearly polarized wave can be dynamically controlled in a range of 1.0 THz-1.6 THz when the conductivity c,F of vanadium dioxide(VO2) is changed under the external stimulation.This study provides an example of actively controlling of the AT and polarization conversion of the EM wave.展开更多
We experimentally demonstrate an electrically triggered terahertz(THz) dual-band tunable band-pass filter based on Si_3 N_4–VO_2–Si_3 N_4 sandwich-structured hybrid metamaterials. The insulator–metal phase transiti...We experimentally demonstrate an electrically triggered terahertz(THz) dual-band tunable band-pass filter based on Si_3 N_4–VO_2–Si_3 N_4 sandwich-structured hybrid metamaterials. The insulator–metal phase transition of VO_2 film is induced by the Joule thermal effect of the top metal layer. The finite-integration-time-domain(FITD) method and finite element method(FEM) are used for numerical simulations. The sample is fabricated using a surface micromachining process,and characterized by a THz time-domain-spectrometer(TDS). When the bias current is 0.225 A, the intensity modulation depths at two central frequencies of 0.56 THz and 0.91 THz are about 81.7% and 81.3%, respectively. This novel design can achieve dynamically electric–thermo–optic modulation in the THz region, and has potential applications in the fields of THz communications, imaging, sensing, and astronomy exploration.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11574059 and 61965005)the National Technology Major Special Project,China(Grant No.2017ZX02101007-003)+2 种基金the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Grant No.2018GXNSFAA050043)the Guangxi Special Expert Program and Innovation Project of Guangxi Graduate Education,China(Grant Nos.2019YCXS088 and 2019YCXS094)the Foundation from Guangxi Key Laboratory of Automatic Detection Technology and Instrument,China(Grant No.YQ16101).
文摘The asymmetric transmission(AT) and polarization conversion of terahertz(THz) wave play a vital role in future THz communication,spectrum,and information processing.Generally,it is very difficult and complicated to actively control the AT of electromagnetic(EM) wave by using traditional devices.Here,we theoretically demonstrate a stereo-metamaterial(stereo-MM) consisting of a layer of metal structure and a layer of phase transition structure with a polyimide spacer in between.The performance of the device is simulated by using the finite-integration-technology(FIT).The results show that the AT and polarization conversion of linearly polarized wave can be dynamically controlled in a range of 1.0 THz-1.6 THz when the conductivity c,F of vanadium dioxide(VO2) is changed under the external stimulation.This study provides an example of actively controlling of the AT and polarization conversion of the EM wave.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11574059,61565004,and 11774288)the National Technology Major Special Project,China(Grant No.2017ZX02101007-003)+2 种基金the Natural Science Foundation of Guangxi,China(Grant Nos.2015GXNSFDA139039 and2017GXNSFBA198116)the Foundation from Guangxi Key Laboratory of Automatic Detection Technology and Instrument,China(Grant No.YQ16101)the Innovation of Guangxi Graduate Education,China(Grant Nos.2018YJCX70,2018YJCX67,and 2018YJCX74)
文摘We experimentally demonstrate an electrically triggered terahertz(THz) dual-band tunable band-pass filter based on Si_3 N_4–VO_2–Si_3 N_4 sandwich-structured hybrid metamaterials. The insulator–metal phase transition of VO_2 film is induced by the Joule thermal effect of the top metal layer. The finite-integration-time-domain(FITD) method and finite element method(FEM) are used for numerical simulations. The sample is fabricated using a surface micromachining process,and characterized by a THz time-domain-spectrometer(TDS). When the bias current is 0.225 A, the intensity modulation depths at two central frequencies of 0.56 THz and 0.91 THz are about 81.7% and 81.3%, respectively. This novel design can achieve dynamically electric–thermo–optic modulation in the THz region, and has potential applications in the fields of THz communications, imaging, sensing, and astronomy exploration.
