On negative reflection in a bianisotropic medium

摘要

The vast parameter space associated with bianisotropic mediums supports a host of complex electromagnetic behaviours. Planewave propagation in a bianisotropic medium is generally characterized by four independent wavevectors. We considered planewave propagation in a Faraday chiral medium (FCM), which is a particular bianisotropic medium that combines natural optical activity with Faraday rotation. FCMs may be theoretically conceptualized as metamaterials arising from the homogenization of isotropic chiral mediums with either magnetically biased ferrites or magnetically biased plasmas. Provided that the magnetoelectric coupling is sufficiently large, there are enhanced possibilities for negative-phase-velocity propagation and therefore negative refraction in FCMs. They can also give rise to the phenomenon of negative reflection. That is, an incident plane wave with positive phase velocity can result in a negatively reflected plane wave with negative phase velocity, as well as a positively reflected plane wave with positive phase velocity. Also, an incident plane wave with negative phase velocity can result in a negatively reflected plane wave with positive phase velocity, as well as a positively reflected plane wave with negative phase velocity.