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Hybrid films incorporating high dielectric constant k ceramics (BaTiO3 and TiO2) in deoxyribonucleic acid (DNA) were fabricated from highly stable dispersions of the ceramic nanoparticles in viscous, aqueous DNA solutions. Dielectric and electrical properties of the as-prepared nanocomposite films were investigated for potential use as gate insulators in organic field effect transistors. A k value as high as 14 was achieved with a 40 wt. % loading of ceramic nanoparticles in DNA. Electrical resistivities on the order of 1014 Ω cm with leakage current densities on the order of 10−9 A/cm2 were measured from current-voltage experiments under electric field biases up to 50 V/μm.

Significant modifications have been made in the processing techniques developed to transform purified, marine-based deoxyribonucleic acid (DNA) into a biopolymer suitable for optical and electronic device fabrication. This technique employs a modified soxhlet-dialysis rinsing process to completely remove excess ionic contaminants from the DNA biopolymer, resulting in a material with greater mechanical stability and enhanced performance reproducibility.

A deoxyribonucleic acid (DNA) biopolymer has been studied for use as a conductive cladding layer in polymer electro-optic (EO) waveguide modulators due to its low optical loss and high electrical conductivity relative to its inorganic polymer counterparts. Electric field contact poling measurements using a DNA biopolymer cladding layer with an amorphous polycarbonate/chromophore (APC/CLD1) guest-host system core layer have been made and compared to a UV15 cladding layer. Using the EO coefficient of APC/CLD1 with no cladding layer as a baseline, the DNA biopolymer cladding layer yielded relative poling efficiencies of 96% while the UV15 poling efficiencies were only 51%.

We report on ultrafast control of the charge state of a single InGaAs quantum dot in a charge-tunable p-i-n diode structure. Focused ion beam etching is employed to decrease the capacitance of the device to enable radio frequency operation. A time-resolved photoluminescence technique is demonstrated that allows monitoring the charge state with a time-resolution which is limited only by the radiative lifetime of the charged and neutral exciton, respectively. Experimental data show that the charge state can be manipulated on time scales shorter than the radiative lifetime of approximately 1.4 ns.