[12p-A409-1~14] 12.4 Organic light-emitting devices and organic transistors

▼ [12p-A409-13] Novel lasing dye having small singlet-triplet energy gap easing the selection of host materials

〇(D)Buddhika Sanjeewa Karunathilaka^1,2, Umamahesh Balijapalli¹, Chathuranganie Senevirathne^1,2, Yu Esaki^1,2, Toshinori Matsushima^2,3, Atula S. D. Sandanayaka^1,2, Chihaya Adachi^1,2,3 (1.OPERA, Kyushu Univ., 2.JST/ERATO, 3.I2CNER, Kyushu Univ.)

Keywords:guest-host system, organic laser gain material, triplet quenching

Quenching of singlets by long lifetime triplets is a serious issue for lasing from organic dyes, especially under long excitation duration. To remove unnecessary triplets, organic laser dyes are often dispersed into a film of a host material having a rather large singlet-triplet energy gap such as anthracene derivatives. However, finding such host materials are limited and another materials combination has been anticipated. In this study, we developed a novel laser dye (DCNP) having a small singlet-triplet energy gap on the basis of the concept of thermally activated delayed fluorescence-based materials. Since the singlet-triplet energy gap of DCNP is as small as 0.44 eV, we can employ BSBCz as a triplet quenching host, i.e., the triplets formed on DCNP are easily transferred to BSBCz. The result would provide an alternative host-guest strategy of fabricating higher-performing laser devices.