ZnO纳米多晶颗粒的受激发射及时间分辨特性

Stimulated emission from nanosized polycrystalline ZnO and its time resolution

以尿素为沉淀剂,采用均匀沉积法与硝酸锌反应获得了 ZnO 的纳米多晶颗粒。在飞秒脉冲激光激发下,观察到了 ZnO 纳米多晶颗粒的受激辐射现象,并从频域和时域两方面研究了 ZnO 纳米多晶的室温激射特性。氧化锌多晶颗粒中出现激子.激子散射导致的激射阈值为7.2 GW·cm^(-2),激射模式类似于 F-P 谐振腔模式,时域谱表现为寿命曲线中出现快速衰减成分。P 带时间衰减具有对称结构,高斯拟合结果只有几个皮秒。

The detailed room-temperature stimulated emission for nanosized polycrystalline ZnO prepared by homogenous precipitation method is investigated by time-resolved spectroscopy.The threshold excitation intensity is 7.2 GW·cm~*-2(and muti-mode lasing behavior is observed which is due to an exciton-exciton collision recombination.And the emission lifetime is drastically reduced.Time-resolved spectrum of P band suggest a Gaussianlike decay time with only a few tens of picoseconds,2 ps,which is the limit of streak camera time resolution.