Integrating Unexpected High Charge‐Carrier Mobility and Low‐Threshold Lasing Action in an Organic Semiconductor

Abstract

AbstractIntegrating high charge‐carrier mobility and low‐threshold lasing action in an organic semiconductor is crucial for the realization of an electrically pumped laser, but remains a great challenge. Herein, we present an organic semiconductor, named as 2,7‐di(2‐naphthyl)‐9H‐fluorene (LD‐2), which shows an unexpected high charge‐carrier mobility of 2.7 cm2 V−1 s−1 and low‐threshold lasing characteristic of 9.43 μJ cm−2 and 9.93 μJ cm−2 and high‐quality factor (Q) of 2131 and 1684 at emission peaks of 420 and 443 nm, respectively. Detailed theoretical calculations and photophysical data analysis demonstrate that a large intermolecular transfer integral of 10.36–45.16 meV together with a fast radiative transition rate of 8.0×108 s−1 are responsible for the achievement of the superior integrated optoelectronic properties in the LD‐2 crystal. These optoelectronic performances of LD‐2 are among the highest reported low‐threshold lasing organic semiconductors with efficient charge transport, suggesting its promise for research of electrically pumped organic lasers (EPOLs).