Adv. Funct. Mater.: Telecom-Wavelength Organic Single-Crystal Lasers Triggered by the Molecular Conformation-Dependent Cascaded Proton Transfer Processes

Title：

Telecom-Wavelength Organic Single-Crystal Lasers Triggered by the Molecular Conformation-Dependent Cascaded Proton Transfer Processes

Authors：

Jun-Jie Wu^1#, Shuwen Yu^2#, Yanping Liu^3#, Chang-Cun Yan¹, Wan-Ying Yang¹, Wanfeng Xie⁴, Xue-Dong Wang¹*, Chaofan Sun⁵*, and Liang-Sheng Liao^1,6*

Institutions：

¹Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, China.

²Division of Energy Research Resources, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China.

³Centre for Chemistry of High-Performance & Novel Materials Department of Chemistry, Zhejiang University, Hangzhou, China.

⁴School of Electrics and Information, Qingdao University, Qingdao, China.

⁵College of Science, Northeast Forestry University, Harbin, China

⁶Macao Institute of Materials Science and Engineering, Macau University of Science and Technology, Macau SAR, China.

Abstract：

Organic semiconductor molecules possess chemical tunability and large stimulated emission cross section, representing a promising candidate for laser gain medium. However, for the pursuit of telecom-wavelength organic lasers, one of the major obstacles is the lack of effective energy-level systems with high optical gain to compensate the exciton deactivation losses. Herein, the effects of molecular conformation-dependent distinct cascaded proton-transfer six-level energy gain systems on lasing emission properties are systematically investigated based on organic polymorphs, proving that an energy-level gain system without reversible transition channels is more conducive to the formation of efficient population inversion and high optical gain. Notably, the one-way irreversible six-level energy system of β-phase polymorph supports more favorable population inversions than the two-way reversible six-level system of α-phase polymorph due to the irreversible excited-state second proton transfer and the irreversible ground state recovery, achieving the amplified spontaneous emission at telecom-wavelength of ≈850 nm. This study provides useful guidelines for constructing efficient energy-level gain systems, promoting the exploration of high-gain organic semiconductor laser materials from visible to near-infrared region.

IF：

19.924

Link：

https://doi.org/10.1002/adfm.202214308