Nanooptics and nanophotonics

Liquid crystal control of the electromagnetic wave propagation through metal-multilayer dielectric structure
Zadorozhnii V.I., Reshetnyak V.Yu.
Taras Shevchenko National University of Kyiv; 64/13, Volodymyrska Street, City of Kyiv, Ukraine, 01601. 
E-mail: v.i.zador@gmail.com .
We consider metal- multilayer dielectric structure consisting of a glass layer, thin silver layer, liquid crystal and alternating high (TiO2) and low (SiO2) refraction index quarter-wave layers (Bragg reflector). There is a layer of SiO2 between the silver layer and the liquid crystal (LC). The tilt angle of the liquid crystal is changed by applying an electrical voltage to the LC layer.    

Fig.1 (left) , (right) .
Under certain conditions, a narrow, deep dip can be observed in the reflectivity spectrum of the system (Fig 1), the spectral position of which can be adjusted by changing the tilt angle of the liquid crystal director. The numerical modeling was carried out using the transfer matrix method. Structures like this may be attractive for various applications, e.g. sensors [1-3].
 
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