Polarization-dependent plasmonic chiral devices

Optical activity is a phenomenon related to the birefringence of light that arises from interactions between a material and the spin state of photons. Pioneering research has shown that, when light passes through a bulk medium with optical activity such as quartz [1] or a solution of chiral molecules, the polarization state of the light can be rotated. Such phenomenon was explained by an interaction of light with the chiral unit cell geometry or chiral molecules [2]. In these materials, the asymmetric response of transmission, according to the direction of the incident light, reveals the possibility of producing a polarization rotator and an optical isolator. In the past, investigators attempted to find materials with stronger optical activity due to the high potential for applications of such materials to optical devices [3]. However, this effort does not appear to have been successful, since controlling the optical properties at the molecular level is a difficult task, due to the small scale of molecules and limitations associated with the chemical processes.