Optical Amplification in Eu $^{3+}$-Doped DNA-Based Biopolymer

Europium (Eu
³⁺
) -doped deoxyribonucleic acid-cetyltrimethylammonium (DNA-CTMA) biopolymers have been prepared and characterized optically. Quartz capillary tube encapsulated Eu
³⁺
-doped biopolymeric waveguides have been fabricated via a simple withdrawal molding technique. Optical amplification at 612-nm wavelength has been demonstrated in these waveguide devices, and the signal enhancements for different lengths of the devices have been measured. A maximum signal enhancement of 24 dB has been obtained for a 15-mm-long device.