Magnetic field-controlled large-angle negative refraction and negative reflection of terahertz waves

Utilizing the generalized multiparticle Mie theory, we address the scattering of an electromagnetic plane wave from a one dimensional array of parallel gyrotropic core-dielectric shell cylinders. Specifically, we examine InSb core-Ge shell cylinders subjected to magnetic fields below 2.3 T. We show that the undesired grating diffraction orders can be suppressed via the interference of electric and magnetic multipoles. The grating offers exciting opportunities for terahertz beam steering: By applying appropriate static magnetic fields, almost perfect transmission, almost perfect reflection, almost perfect absorption, large-angle negative refraction and large-angle negative reflection of terahertz waves are achievable. Indeed, deflection angles as large as 158^∘ are realizable.