Deep blue widely tunable organic solid-state laser based on a spirobifluorene derivative

TLDR

The study demonstrates amplified spontaneous emission and optically pumped deep‑blue lasing in the spirobifluorene derivative 2,7‑bis(biphenyl‑4‑yl)-2′,7′‑di‑tert‑butyl‑9,9′‑spirobifluorene. The laser is achieved by depositing thin films of the compound on a distributed‑feedback grating substrate, enabling solid‑state lasing. The device exhibits a tunable emission range of 401.5–434.2 nm, with a record short‑wavelength edge at 401.5 nm, a low threshold of 83 μJ cm⁻², and demonstrates the compound’s suitability as a blue‑emitting diode laser.

Abstract

We report on amplified spontaneous emission and optically pumped deep blue lasing in the organic spirobifluorene derivative 2,7-bis(biphenyl-4-yl)-2′,7′-di-tert-butyl-9,9′-spirobifluorene. Solid-state lasing is observed in thin films of this material deposited on a distributed-feedback (DFB) grating substrate. The laser wavelength can be tuned from 401.5 to 434.2 nm depending on the grating period of the Bragg reflector. The blue edge of this interval at 401.5 nm makes this laser an extremely short wavelength organic DFB laser. When pumping with a pulsed nitrogen laser at 337 nm, we observe a laser threshold energy density of 83 μJ/cm2. These results render this spiro compound an excellent candidate for blue-emitting diode lasers.