A photo-driven dual-frequency addressable optical device of banana-shaped molecules

作者：Prasad S Krishna^*; Madhuri P Lakshmi; Hiremath Uma S; Yelamaggad C V

来源：Applied Physics Letters, 2014, 104(11): 111906.

DOI：10.1063/1.4869224

We propose a photonic switch employing a blend of host banana-shaped liquid crystalline molecules and guest photoisomerizable calamitic molecules. The material exhibits a change in the sign of the dielectric anisotropy switching from positive to negative, at a certain crossover frequency of the probing field. The consequent change in electric torque can be used to alter the orientation of the molecules between surface-determined and field-driven optical states resulting in a large change in the optical transmission characteristics. Here, we demonstrate the realization of this feature by an unpolarized UV beam, the first of its kind for banana-shaped molecules. The underlying principle of photoisomerization eliminates the need for a second driving frequency. The device also acts as a reversible conductance switch with an order of magnitude increase of conductivity brought about by light. Possible usage of this for optically driven display devices and image storage applications is suggested.

• 出版日期2014-3-17