Development of an all-DNA-surfactant electro-optic modulator

Marine-based deoxyribonucleic acid (DNA), purified from waste products of the Japanese fishing industry, has recently become a new material of interest in photonics applications. The water soluble DNA is precipitated with a surfactant complex, cetyltrimethl-ammonium chloride (CTMA), to form a water insoluble complex, DNA-CTMA, for application as a nonlinear optical material. It is possible to fabricate an all-DNA-CTMA waveguide by crosslinking the DNA-CTMA. Crosslinking causes the material to become resistant to its initial solvents upon curing; this allows a core layer of crosslinked DNA-CTMA-chromophore to be spin coated directly on top of a cladding layer of crosslinked DNA-CTMA. The chromophore dye provides for the electro-optic effect to be induced through contact poling. The chromophore also raises the index of refraction of the core layer above that of the cladding needed for waveguiding. Progress on the development of this all-DNA-CTMA electro-optic modulator is presented.