Abstract
We present a theoretical analysis of optical diffractive properties of magnetically tunable optical transmission gratings composed of periodically assembled layers of a polymer and a ferromagnetic liquid crystal (LC). The orientational structure of the LC layers as a function of an applied magnetic field is calculated by minimization of the Landau-de Gennes free energy for ferromagnetic LCs, which is performed numerically and also analytically by using the one-constant approximation and the approximations of the high and the low magnetic fields. Optical diffractive properties of the associated diffraction structure are calculated numerically in the framework of rigorous coupled-wave analysis (RCWA). The presented methodology provides a basis for designing new types of diffractive optical element based on ferromagnetic LCs and simulating their operation governed by the in-plane magnetic field.
Highlights
Optical gratings are central components of diffractive optical elements (DOEs) that are used in various optical devices to manipulate optical beams in order to create a desired far-field intensity profile of the beam
We present a theoretical analysis of optical diffractive properties of magnetically tunable optical transmission gratings composed of periodically assembled layers of a polymer and a ferromagnetic liquid crystal (LC)
The presented methodology provides a basis for designing new types of diffractive optical element based on ferromagnetic LCs and simulating their operation governed by the in-plane magnetic field
Summary
Optical gratings are central components of diffractive optical elements (DOEs) that are used in various optical devices to manipulate optical beams in order to create a desired far-field intensity profile of the beam. Recent investigations have shown that doping with ferromagnetic nanoplatelets induces the formation of a ferromagnetic nematic LC phase [31,32], which enables LC reorientation with magnetic fields as low as a few mT [33] Such LCs are very attractive for the construction of various kinds of magneto-optical device, among them magnetically tunable DOEs. In this work, we present a theoretical analysis of optical diffractive properties of magnetically tunable optical diffraction gratings based on ferromagnetic LCs. The orientational structure of the LC medium in a periodic polymeric scaffold as a function of an applied magnetic field is calculated by minimization of the Landau-de Gennes free energy for ferromagnetic LCs [34,35], while optical diffractive properties of the associated diffraction structure are calculated by the use of rigorous coupled-wave analysis (RCWA) [36,37,38,39]. We show that the presented methodology can be used to design new types of DOE based on ferromagnetic LCs and simulate their operation governed by the in-plane magnetic field
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
