In this paper we report a detailed characterization of a new structure (POLICRYPS) in which liquid crystal films are completely separated by polymer slices. This structure behaves as a Bragg diffraction grating and exhibits efficiencies that can become as high as 96-98%. The temperature dependence of the diffraction efficiency can be explained in terms of a Kogelnik-like model. A numerical simulation has been implemented which makes use only of real values of physical quantities and accounts for the experimental results with good accuracy. An applied electric field is able to switch off the grating, with a characteristic switching time which is lower than 1 ms. Threshold values of the field vary in the range 3-5 V/μm for gratings with a 1.39 μm fringe spacing.

Realization of POLICRYPS Gratings: Optical and Electro-Optical Properties

CAPUTO, Roberto;UMETON, Cesare Paolo
2005

Abstract

In this paper we report a detailed characterization of a new structure (POLICRYPS) in which liquid crystal films are completely separated by polymer slices. This structure behaves as a Bragg diffraction grating and exhibits efficiencies that can become as high as 96-98%. The temperature dependence of the diffraction efficiency can be explained in terms of a Kogelnik-like model. A numerical simulation has been implemented which makes use only of real values of physical quantities and accounts for the experimental results with good accuracy. An applied electric field is able to switch off the grating, with a characteristic switching time which is lower than 1 ms. Threshold values of the field vary in the range 3-5 V/μm for gratings with a 1.39 μm fringe spacing.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/20.500.11770/153236
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 2
  • ???jsp.display-item.citation.isi??? 1
social impact