Analytical modeling of compound metallic reflection gratings

The transmission and reflection of electromagnetic waves impinging on metallic surfaces with periodically distributed slits (diffraction gratings) have been the subject of thorough studies using numerical and experimental approaches. Of special interest are the properties of the so-called compound gratings, which are periodic arrays of slits whose unit cell contains several of them. The transmission properties of such diffraction gratings have been studied along the last few years both theoretically (D.C. Skigin and R.A. Depine, Phys. Rev. Lett., 95, 217402, 2005) and experimentally (A.P. Hibbins et al., Phys. Rev. Lett., 96, 257402, 2006; M. Navarro-Ca et al., App. Phys. Lett., 94, 091107, 2009). However, analytical models are very useful for design purposes and, moreover, they provide physical insight that is not obvious from numerical approaches. For compound transmission gratings, the authors of this contribution recently developed a circuit-model-based analytical approach (F. Medina, F. Mesa and D.C. Skigin, IEEE Trans. on Mic. Theory Tech., 58, 105-115, 2010) that captures the essential physics of these optical systems. Thus, compound transmission gratings are now well understood, and numerical or analytical design tools are available.