论文标题
胶体量子点薄膜光致发光的电压控制的可逆调节
Voltage-Controlled Reversible Modulation of Colloidal Quantum Dot Thin Film Photoluminescence
论文作者
论文摘要
量子点薄膜光致发光（PL）的主动调制在生物医学和光电系统中具有深远的潜在应用，但是在实现较大的PL调制深度和快速的时间响应方面仍然存在挑战。在这里，我们通过在反向偏置下的量子点发光二极管（QD-LED）中的光学激发胶体量子点薄膜（QD-LED）中的光学激发胶体量子点薄膜，报告了有效的电压控制的光学下接口。利用场诱导的发光猝灭，我们表明大型电场可以在该纳米结构设备中强烈修改载体动力学，从而导致稳定且可逆的光致发光淬火。该设备在300 mV/cm的施加电场下，表现出高达99.5％的光致发光降低，对应于200：1的对比度，纳秒响应时间为300。使用激发波长依赖性和瞬态PL光谱法，我们进一步表明，通过量子限制的Stark效应（QCSE）（QCSE）和野外诱导的激子分离的协同相互作用来实现高度的淬火。
Active modulation of quantum dot thin film photoluminescence (PL) has far-reaching potential applications in biomedical and optoelectronic systems, but challenges remain in achieving large PL modulation depth and fast temporal response. Here we report an efficient voltage-controlled optical down-converter by optically exciting a colloidal quantum dot thin film within a quantum dot light-emitting diode (QD-LED) under reverse bias. Utilizing field-induced luminescence quenching, we show that a large electric field can strongly modify carrier dynamics in this nanostructured device, resulting in stable and reversible photoluminescence quenching. The device exhibits photoluminescence reduction of up to 99.5%, corresponding to a contrast ratio of 200:1, under the applied electric field of 3 MV/cm, with a 300 nanosecond response time. Using excitation wavelength dependent and transient PL spectroscopy, we further show that the high degree of quenching is achieved by a synergistic interplay of quantum-confined Stark effect (QCSE) and field-induced exciton dissociation.
