2026-05-31T10:57:41Zhttps://riuma.uma.es/rest/oai/request

oai:riuma.uma.es:10630/176102026-02-03T12:10:49Zcom_10630_2254col_10630_37959

Designing polarization management devices by tilting subwavelength grating structures Luque-González, José Manuel Herrero-Bermello, Alaine Ortega-Moñux, Alejandro Molina-Fernández, Íñigo Velasco, Aitor V. Cheben, Pavel Schmid, Jens H. Wang, Shurui Halir, Robert Optica integrada Materiales ópticos Metamateriales Subwavelength gratings (SWG) are periodic structures which behave as controllable homogeneous metamaterials. SWGs are extremely interesting when they are used in platforms with a limited choice of material refractive indices, enabling the design of a myriad of high-performance devices. Here we present a novel technique to gain control over the intrinsic anisotropy of the synthesized metamaterial. We show that tilting the silicon segments in a SWG structure mainly affects the in-plane (TE) modes, with little impact on the out-of-plane (TM) modes. Moreover, we present a methodology to quickly but accurately calculate the modes of a tilted periodic structure modeling the structure as a rotated uniaxial crystal which can be solved with an anisotropic mode solver. Measurements on a set of fabricated tilted SWG waveguides validate our simulation results. By using the presented technique, we design a polarization beam splitter based on a 2x2 multimode interferometer. The design is based on the optimization of the tilting angle to tone the beat length of the TE modes to be a half of the beat length of the TM modes. 2019-05-03T06:28:06Z 2019-05-03T06:28:06Z 2019 2019-05-03 conference output https://hdl.handle.net/10630/17610 eng SPIE Optics + Optoelectronics Praga, República Checa 1-4 de abril de 2019 open access