Planar photonic crystals infiltrated with liquid crystals: optical characterization of molecule orientation

Abstract

Nematic liquid crystals are infiltrated into InP-based planar photonic crystals. Optical measurements as a function of temperature and polarization are used to study the average director field configuration in the nanometer-size holes: a planar equilibrium state is found.

Liquid Crystals into Planar Photonic Crystals

“…electric field perpendicular and parallel to the hole axis, respectively: see Fig. 5a) and the effective refractive indexes n eff for both the TE and the TM guided modes varies linearly with temperature Ferrini et al, 2004;Mulot et al, 2004;Martz et al, 2005;Ferrini et al, 2006;El-Kallassi et al, 2007). The internal light source (ILS) technique was used to optically characterize the infiltrated PhC structures (Ferrini et al, 2002b).…”

“…Both theoretical and experimental studies have been performed to quantify the influence of the surface anchoring and of the hole size on the LC molecular organization (Crawford et al, 1991a-b;Marroum et al, 1995;Burylov, 1997). With regard to this issue, we will show how optical measurements as a function of temperature and polarization can yield information on both the hole filling and the molecule orientation Ferrini et al, 2006). In Section 4, we will show how the optical response of PhC devices infiltrated with nematic LCs can be tuned by temperature, electric field and optical irradiation El-Kallassi et al, 2007).…”

“…Among the numerous techniques that have been proposed, infiltrating the air pores of a PhC with a synthetic organic material that has a tunable refractive index (e.g. liquid crystals, polymers, liquids, and liquid dispersions of colloidal quantum dots) has proved to be one of the most promising approaches for both trimming and tuning (Busch & John, 1999;Yoshino et al, 1999b;Leonard et al, 2000;Kubo et al, 2002;Gottardo et al, 2003;Mertens et al, 2003;Schuller et al, 2003;Maune et al, 2004;Mingaleev et al, 2004;Weiss et al, 2005a;Erickson et al, 2006;Ferrini et al, 2006;Haurylau et al, 2006a-b;Intonti et al, 2006;Martz et al, 2006;Tomljenovic-Hanic et al, 2006;van der Heijden et al, 2006a;Barthelemy et al, 2007;Smith et al, 2007;Tay et al, 2007). The effect of infiltrating a PhC with a low refractive index material is qualitatively shown in Fig.…”

“…In particular, the potential of PhC infiltration with nematic liquid crystals (LCs) has been largely demonstrated for one-, two-and three-dimensional (1D, 2D and 3D) PhCs. Therefore, besides their classical fields of application, LCs are also having a strong impact in the PhC field (Busch & John, 1999;Yoshino et al, 1999b;Leonard et al, 2000;Kang et al, 2001;Shimoda et al, 2001;Kubo et al, 2002;Mertens et al, 2002;Gottardo et al, 2003;Mertens et al, 2003;Schuller et al, 2003;Weiss & Fauchet, 2003;Busch et al, 2004;Du et al, 2004;Kubo et al, 2004;Martz et al, 2004;Maune et al, 2004;Kosmidou et al, 2005;Lourtioz et al, 2005;Maune et al, 2005;Weiss et al, 2005a-b;Ferrini et al, 2006;Haurylau et al, 2006b;.…”

All-optical switching, bistability, and slow-light transmission in photonic crystal waveguide-resonator structures

“…The solution to this could be the embedding of such highly nonlinear but low-index materials into a host photonic crystal made of a high-index semiconductor. Optimized waveguding designs for the basic functional devices of this kind are available [33][34][35] and recent experimental progress [36,37] may soon allow a realization of corresponding linear and nonlinear devices.…”