Optical properties of deoxyribonucleic acid (DNA) and its application in distributed feedback (DFB) laser device fabrication

The chemical structure of deoxyribonucleic acid, or DNA, is a unique double helix structure. This structure has nanoscale features that could improve device performance. Dopants were introduced into such a nanoscale structure to obtain enhanced optical luminescence performance. The thin film process of DNA was studied. High optical quality thin film was made of surfactant-reacted DNA material (DNA-CTMA). Thin film optical properties including transmission, optical waveguide loss, and index of refraction were studied and results showed that the DNA-CTMA material has a very low optical loss in both visible and infrared (IR) spectra. Surface morphology studies showed that the DNA-CTMA thin film is a good candidate for optical device fabrication.; Sulforhodamine 640 (SRh) laser dye was doped in DNA-CTMA thin film. Such a doped thin film showed enhanced photoluminescence over PMMA material. Mechanism of enhanced performance was discussed and examined experimentally. Interference lithography was chosen for distributed feedback (DFB) laser device fabrication on SRh doped DNA-CTMA thin film. Both DNA-CTMA:SRh and PMMA:SRh DFB devices showed stimulated emission while DNA-CTMA material has lower threshold and higher efficiency than PMMA.