TY - JOUR T1 - Highly Flexible and Tunable Coherent Perfect Absorption in Graphene Metasurface at Wide Angle of Incidence in Terahertz Regime TT - جذب همدوس کامل توسط متاسطح گرافینی قابل انعطاف و تنظیم‌پذیر در بازه وسیع زاویه‌ تابش در بازه تراهرتز JF - opsi JO - opsi VL - 24 IS - 0 UR - http://opsi.ir/article-1-1448-en.html Y1 - 2018 SP - 793 EP - 796 KW - Coherent perfect absorption KW - Graphene KW - Metasurface KW - Modulation KW - Terahertz N2 - We exploit graphene square-ring to realize coherent perfect absorption (CPA) in the terahertz (THz) regime. The simulated results show a 90% absorption coefficient over a wide range of angles of incidence for both TE and TM radiations. The coherent absorptivity is tunable from nearly 0% to 100% by adjusting the relative phase of two low power counter-propagating coherent beams. The central frequency of the absorption simply can be tuned by varying the chemical potential of graphene and by changing the geometric parameters of metasurface. Thus, the proposed absorber is very promising for various optical applications as modulators, detectors and electromagnetic switches. This article offers a novel path for perfect absorption in THz gap, it should be noted that the thickness of proposed absorber is only about λ/4. M3 ER -