Efficient manipulation of terahertz waves by multi-bit coding metasurfaces and further applications of such metasurfaces

• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（2）
• 所属期刊栏目: ELECTROMAGNETISM,OPTICS,ACOUSTICS,HEAT TRANSFER,CLASSICAL MECHANICS,AND FLUID DYNAMICS
• 页码范围: 378-386
• 页数: 9页
• 语种: 英文
• DOI: 10.1088/1674-1056/abd6fc

摘要

Benefiting from the unprecedented superiority of coding metasurfaces at manipulating electromagnetic waves in the microwave band,in this paper,we use the Pancharatnam-Berry(PB)phase concept to propose a high-efficiency reflective-type coding metasurface that can arbitrarily manipulate the scattering pattern of terahertz waves and implement many novel functionalities.By optimizing the coding sequences,we demonstrate that the designed 1-,2-,and 3-bit coding metasurfaces with specific coding sequences have the strong ability to control reflected terahertz waves.The two proposed 1-bit coding metasurfaces demonstrate that the reflected terahertz beam can be redirected and arbitrarily controlled.For normally incident x-and y-polarized waves,a 10 dB radar cross-section(RCS)reduction can be achieved from 2.1 THz to 5.2 THz using the designed 2-bit coding metasurface.Moreover,two kinds of orbital angular momentum(OAM)vortex beams with different moduli are generated by a coding metasurface using different coding sequences.Our research provides a new degree of freedom for the sophisticated manipulation of terahertz waves,and contributes to the development of metasurfaces towards practical applications.