Simulation and Analysis of a Tunable Polarization Converter Based on Dirac Semimetals
This paper proposes a dynamic metamaterial structural polarization converter based on bulk Dirac semi-metal(BDS).Different from the traditional polarization converter,the polarization conversion ratio and asymmetric trans-missions of this polarization converter can be adjusted by Fermi level.The simulation results show that when the Fermi lev-el of BDS are adjusted at 90 meV,the polarization conversion ratio is greater than 90%in the frequency range of 1.085～1.872 THz(Bandwidth is 0.787 THz).The polarization conversion ratio is peaked at 98%at the 1.159 THz.The asymmet-ric transmissions of this polarization converter is greater than 60%in the big frequency range of 1.229～1.831 THz.BDS can be controlled by Fermi energy,that explained the control mechanism of polarization conversion rate and the asymmetric transmission.The polarization rotation angle,ellipticity angle,surface current and electric field distribution are studied to clarify the physical mechanism of polarization deflection.By applying gate voltage to control the Fermi level of BDS,the dynamic tuning of polarization conversion rate and asymmetric transmission of the polarization converter is realized.The tunable asymmetric transmission characteristics of this polarization converter provide a new idea for the manufacture of multiplexers,THz diodes and other equipment.
国家科技期刊平台
NSTL
万方数据
