They also designed a device structure with a mixed-order distributed feedback grating sitting on top of one of the electrodes used to inject electricity into the organic thin films. The grating alternated first- and second-order Bragg scattering regions in order to provide strong lateral optical feedback and efficient vertical outcoupling of the laser emission. It was further
optimized to also control the flow of electricity in the devices and minimize the amount of electricity required to observe lasing from the organic thin film.
Electrically driven under pulse operation, the organic semiconductor laser diode (OSLD) exhibited spectral line narrowing with increasing current density, with lasing occurring at the long-wavelength band edge (480.3nm) of the Bragg stopband.
Last March, the researchers have founded a startup called KOALA Tech Inc. (short for Kyushu Organic Laser Technology Inc.) and plan to overcome the final obstacles to the commercialization of organic laser diodes which they anticipate could be simple to manufacture, cheap, and tunable. Such organic laser diodes could then be integrated into other organic-based optoelectronic platforms for low cost spectroscopy, displays, medical devices and LIFI telecommunications.
Kyushu University - www.kyushu-u.ac.jp