A new light-intensity-dependent Brewster angle caused by programmed defects Original Research Article

It is known that by using induced electric and magnetic dipole moments as the microscopic sources for the macroscopic optical phenomena, both the Fresnel equations and consequently, the Brewster angle formula, can be rigorously reproduced. Motivated by such physical intuition and mathematical rigor, we demonstrate that novel materials of variant Brewster angles can be created by embedding, within selected uniform isotropic host materials, pre-determined, optically responsive defects at the prescribed orientations in the form of permanent dipoles. Following this, a peculiar incident-light-intensity-dependent Brewster angle (θB) is discovered. In addition, it is even possible to render θB=0 via proper manipulation of the permanent polarization strength and its orientation, as well as the magnetic permeability. The feasibility of such active modifying approach using pre-determined defects should be very much enhanced as we are entering the era of nanometer technologies. Thus, we will not be surprised to see the birth of various new materials, novel devices and applications originated from such defect-engineering approach, in the coming days.