Evidence of birefringence and anomalous electromagnetic-pulse propagation in an organic light-emitting diode

Abstract

dHigh-speed electromagnetic characteristics of an organic light-emitting diode (OLED) are explored in this paper. When a high-frequency (similar to 14 GHz) microwave pulse is injected into an OLED, the pulse is split into two peaks: one peak is delayed by 1.725 ns and another one is advanced by 0.183 ns, which also suggests the existence of an extremely low-speed group velocity. The effective thickness of the OLED sample is similar to 355.8 nm and, as a result, the effective index of refraction is similar to 107 when the splitting phenomenon occurs. (c) 2005 Wiley Periodicals, Inc.