[19a-C212-1~10] 12.4 有機EL・トランジスタ

▲ [19a-C212-3] A current-injection organic semiconductor laser diode

〇SANGARANGE DONATULA SANDANAYAKA^1,2,5、Toshinori Matsushima^1,2,3,5、Fatima Bencheikh^1,2,5、Shinobu Terakawa^1,2,5、William J. Potscavage, Jr.^1,2,5、Chuanjiang Qin^1,2,5、Takashi Fujihara^1,4,5、Kenichi Goushi^1,2,5、Jean-Charles Ribierre^1,2,5、Chihaya Adachi^1,2,3,4,5 (1.OPERA、2.JST/ERATO、3.I2CNER、4.ISIT、5.Kyushu University)

キーワード：laser diode, organic semiconductor, current-injection

In this study, the lasing properties of 4,4’-bis[(N-carbazole)styryl]biphenyl (BSBCz)¹ thin films under electrical pumping are investigated. Present laser diodes are primarily based on inorganic semiconductors, but organics can also be excellent gain media with unique fabrication routes. However, electrically driven organic semiconductor laser diodes have not yet been realized despite advances in optically pumped organic semiconductor lasers. Here, we report the first demonstration of organic semiconductor laser diodes (Fig. 1). The devices incorporate a mixed-order distributed feedback SiO₂ grating in an organic light-emitting diode structure and emit blue lasing. These results prove that lasing by direct injection of current into an organic thin film can be achieved through selection of a high-gain organic semiconductor showing clear separation of the lasing wavelength from significant triplet² and polaron absorptions and design of a proper feedback structure to suppress losses at high current densities.³ This represents the first step toward simple organic-based laser diodes that can cover the visible and near infrared spectra and a major advance toward future organic optoelectronic integrated circuits.