Near-infrared absorption-emission cross-sections of PbSe quantum dots doped in UV gel

作者：Cheng, Cheng^*; Xu, Yinhui; Cheng, Xiaoyu

来源：Optics Communications, 2015, 347: 108-112.

DOI：10.1016/j.optcom.2015.02.034

• PbSe quantum dot
• Absorption cross-section
• Emission cross-section
• Doping concentration
• Wavelength dependence

We measure near-infrared absorption spectra of PbSe quantum dots (QDs) with three sizes (4.5, 5.0, and 5.6 nm) doped in UV gel with the concentration of 0.25-1.50 mg mL(-1) by using an absorption-spectrum method. An empirical formula is proposed to describe the correlation of the first-second absorption-peak wavelengths and QD size. The peak-absorption cross-section is measured as 2.76-3.69 x 10(-16) cm(2) for 5.6-nm QD, and the absorption coefficient ranges in 0.19-0.59 cm(-1), both associated with the doping concentration and the QD size. Furthermore, the emission cross-sections are determined by measuring the photoluminescence spectra of QDs and using the McCumber relationship, which depend weakly on both the doping concentration and the QD size. For 5.6-nm QD, the measured peak-emission cross-section is 336-4.48 x 10(-16) cm(2) within the range of experimental doping concentration.

• 出版日期2015-7-15
• 单位浙江工业大学