低浓度掺杂CdSe/ZnS量子点光纤光致荧光光谱特性研究

Study on Photoluminescence Spectra of a(CdSe/ZnS) Quantum-dot Doped Fiber in Low Doped Concentrations

制备了一种半导体量子点CdSe/ZnS低浓度掺杂的光纤,测量了不同掺杂浓度和不同光纤长度下光纤出射端的光致荧光光谱,分析了掺杂光纤长度和浓度对量子点光纤荧光光谱特性的影响.结果表明,与掺入光纤前相比,光纤中的量子点荧光发射峰值波长出现红移.在掺杂光纤长度为1～20cm和掺杂浓度为(0.33～2.5)×10-2mg/mL的实验范围内,红移量随着掺杂光纤长度的增加和掺杂浓度的提高而增大.对给定的激励功率,荧光发射峰值强度对应有一个最佳的量子点光纤长度.对于给定的量子点光纤长度,荧光发射峰值强度对应有一个最佳的量子点掺杂浓度.

Photoluminescence （PL） spectra of a CdSe/ZnS-quantum dot （QD）-doped fiber in low doped concentrations were investigated by measuring the PL spectra of the QD-doped fiber with different fiber lengths and doped concentrations. Effects of the fiber length and the doped concentration on the spectra were discussed. Compared with the measured PL spectra of the QD before doping into the fiber,a red shift of the PL-peak wavelength occured after doping due to a re-absorption/excitation effect in the fiber configuration. Such a red shift was enhanced with the increase of the fiber length and the doped concentration. Also, the PL-peak intensity could arrive in a maximum at a fiber length and in a doped concentration for the given exciting intensity.