微腔效应影响有机发光器件调制带宽特性研究

Microcavity Effect on Modulation Bandwidth Characteristics in Organic Light-emitting Diodes

可见光通信(VLC)技术巧妙地融合了通信和照明或显示功能,为通信提供了高效便捷的方案。有机电致发光器件(OLED)作为最接近自然阳光的人造光源,在可见光通信系统的发射端展现出巨大的应用潜力。然而,受制于有机发光染料激子辐射复合速率较慢的限制,OLED在高频信号激励时响应速度较慢。为了克服这一限制,我们提出利用微腔结构,旨在通过微腔效应增强有机发光分子的自发辐射速率,从而改善器件的频率响应。研究结果表明,特定腔长的光学微腔引发的Purcell效应能够提升特定波长的光子态密度,从而加速其自发辐射速率。这种增强效应成功地将调制带宽从4 kHz提高到7 kHz,拓展了近75%的响应频率范围。

Visible light communication(VLC)technology ingeniously integrates communication and illumination or display,providing an efficient and convenient solution for communication.Organic light-emitting diodes(OLEDs),serving as an artificial light source closest to natural sunlight,exhibit tremendous application potential at the transmitter end of VLC systems.However,constrained by the slow radiative recombination rate of organic lumi⁃nescent dyes,OLEDs always demonstrate a sluggish response speed under high-frequency signal excitation.To over⁃come this limitation,we propose the utilization of a microcavity structure with the aim of enhancing the spontaneous emission rate of organic emitters through the microcavity effect,thereby improving the devices frequency response.Research results indicate that the Purcell effect induced by an optical microcavity with a specific cavity length can el⁃evate the photon density at the emitter position,accelerating its spontaneous emission rate.This enhancement success⁃fully increases the modulation bandwidth from 4 kHz to 7 kHz,expanding the response frequency range by nearly 75%.