Appl. Phys. Lett. 99, 253301 (2011)

Yu-Chueh Hung and co-workers in Taiwan and Germany have demonstrated a write-once, read-many-times organic memory device composed of a 90-nm-thick DNA biopolymer nanocomposite layer loaded with a silver precursor and sandwiched between two electrodes. Irradiating the device with 365 nm ultraviolet light at an intensity of 3.5 mW cm−2 caused silver nanoparticles to form through a thermally driven process of light-induced growth. The device exhibited good charge retention properties and became highly conductive above a threshold voltage of 2.6 V. The researchers also found that the device exhibited no significant change in conductivity in either its 'on' or 'off' states during the testing period of 105 s. This facile technique, which takes advantage both of DNA's affinity for silver ions and the ease with which DNA films can be formed through spin-coating, can be used to manipulate the properties of DNA nanocomposite thin films, and therefore holds great promise for optical storage and plasmonic applications.