Fluorescence and amplified emission properties of single-crystal 2,5-bis(4-biphenylyl)thiophene

ABSTRACT

Ligth amplification properties are investigated for single crystals of commercially available 2,5-bis(4-biphenylyl)thiophene. Depending on growth methods, three kinds of crystals are obtained having different fluorescence spectra in blue-green color. Under optical pumping, their amplified spontaneous emission (ASE) bands appear at different wavelengths. The solution-grown crystal shows ASE bands at λ = 464 and 494 nm which are assigned to the 0–1 and 0–2 transitions, respectively. By contrast, the vapor- and slide-boat-grown crystals show a red-shifted 0–1 band at λ = 496 and a 0–2 band at 520 nm, respectively.

KEYWORDS:

• 2,5-bis(4-biphenylyl)thiophene
• single crystal
• fluorescence
• amplified spontaneous emission
• organic laser

Acknowledgments

This work was supported by Grant-in-Aid for Scientific Research (B) No. 25286042 from Japan Society for the Promotion of Science (JSPS) and the Green Photonics project of Nara Institute of Science and Technology.