Voltage-controlled multiguide directional coupler formed in a planar nematic liquid crystal film

Ming-Shan Tsai; Chie-Tong Kuo; Shuan-Yu Huang; Chia-Chi Shih; I-Min Jiang
August 2004
Applied Physics Letters;8/9/2004, Vol. 85 Issue 6, p855
Academic Journal
A voltage-controllable multiguide directional coupler is designed with a nematic liquid crystal cell, comprising a grating-like indium-tin-oxide electrode. An incident polarized laser beam can couple into adjacent channels by periodic distribution of the refractive index. This capability is attributed to the reorientation of the periodic liquid crystal caused by the application of a voltage. The coupling variation of the optical power in the transverse direction parallel to the waveguide surface is investigated. This work presents a promising coupling function for potential applications of optical communication devices.


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