ABSTRACT
A series of benzo[ghi]perylene (Bp) and coronene (Cor) derivatives substituted with electron-withdrawing methoxycarbonyl (COOMe) or electron-donating methoxyl (MeO) groups was synthesized. The electrochemical, spectroscopic, and photophysical properties of these compounds were investigated by cyclic voltammetry, steady-state and time-resolved spectroscopy, and quantum-yield measurements. Introduction of suitable substituents onto the aromatic rings enabled control of electrochemical and spectroscopic behavior. Examination of excited-state dynamics revealed that fluorescence quantum yields increased with increasing number of COOMe groups in both Bp and Cor derivatives, consistent with the findings of DFT calculations. Single-crystal analysis allowed the performance of field-effect transistors containing single crystals of the derivatives to be rationalized.
ABSTRACT
Organic light-emitting transistors (OLETs) are of great research interest because they combine the advantage of the active channel of a transistor that can control the luminescence of an in-situ light-emitting diode in the same device. Here we report a novel single-crystal OLET (SCLET) that is coupled with single crystal optical feedback resonators. The combination of single-crystal waveguides with native Fabry-Perot cavities, formed by parallel crystal edges, drastically lowers the threshold energy for spectral narrowing and non-linear intensity enhancement. We apply this structure to SCLETs and demonstrate the first fabrication of a SCLET with the optical feedback resonators.
Subject(s)
Lighting/instrumentation , Micro-Electrical-Mechanical Systems/instrumentation , Optical Devices , Organic Chemicals/chemistry , Transistors, Electronic , Equipment Design , Equipment Failure Analysis , FeedbackABSTRACT
Extremely high current densities are realized in single-crystal ambipolar light-emitting transistors using an electron-injection buffer layer and a current-confinement structure via laser etching. Moreover, a linear increase in the luminance was observed at current densities of up to 1 kA cm(-2) , which is an efficiency-preservation improvement of three orders of magnitude over conventional organic light-emitting diodes (OLEDs) at high current densities.
