物理学报2025，Vol.74Issue(13)：425-434,10.DOI:10.7498/aps.74.20241762
透反双模态极化转换与超宽带吸收功能可调控太赫兹超表面理论设计
Theoretical design of tunable terahertz metasurfaces with dual-mode polarization conversion and ultra-broadband absorption functionality
摘要
Abstract
In this paper,we propose a vanadium dioxide and germanium telluride composite metasurface.The conductivity of vanadium dioxide and germanium telluride is varied by changing the temperature,which enables the switching of functions such as ultra-broadband absorption,reflective-type polarization,and transmissive-type polarization.When vanadium dioxide is metallic and germanium telluride is crystalline,the terahertz wave is incident along the-z direction,and the metasurface can be used as a broadband absorber,with an absorption rate greater than 90％in a frequency range of 7.96-17.76 THz,and the absorption bandwidth reaches 9.8 THz,with a relative bandwidth of 76.2％.In addition,the designed metasurface absorber is polarization-insensitive and exhibits good absorption performance at large incidence angles.Terahertz waves are incident along the+z direction,and this metasurface can be used as a reflective polarization converter with a polarization conversion ratio greater than 0.9 for x-and y-polarized waves in the frequency band from 2.04 to 4.44 THz.The effects of incidence angle and structural parameters on polarization conversion performance are also investigated.When vanadium dioxide is in the dielectric state and germanium telluride is in the amorphous state,the metasurface can be used as a transmissive polarization converter,with a polarization conversion rate of greater than 0.9 in a frequency band of 0.65-5.07 THz.And the high polarization conversion performance can be maintained in a wide range of incidence angles.Finally,the physical mechanism of polarization conversion is analyzed using surface currents.The results show that the metasurface structure has bi-directional,switchable and multi-functional characteristics for terahertz wave manipulation,and has broad application prospects in terahertz wave sensing,imaging and communication.关键词
反射极化转换/透射极化转换/超宽带吸收/超表面Key words
reflective polarization conversion/transmissive polarization conversion/ultra-broadband absorption/metasurface引用本文复制引用
王丹,李九生,熊日辉..透反双模态极化转换与超宽带吸收功能可调控太赫兹超表面理论设计[J].物理学报,2025,74(13):425-434,10.基金项目
国家自然科学基金(批准号:62271460,62435017)和浙江省自然科学基金重点项目(批准号:LZ24F050005)资助的课题. Project supported by the National Natural Science Foundation of China(Grant Nos.62271460,62435017)and the Natural Science Foundation of Zhejiang Province,China(Grant No.LZ24F050005). （批准号:62271460,62435017）
