Fig. 1. Steady-state absorption (solid-line) and fluorescence (dash-line) spectrum of QDs sample. Inset: energy level diagram illustrating the relevant energy of electron/hole states and allowed optical transitions (diagram not drawn to scale).样品的稳态吸收光谱(实线)和稳态荧光光谱(虚线), 其中插图部分为样品的能带跃迁示意图

Fig. 2. Femtosecond time-resolved transient absorption (TA) spectra at 365 nm excitation with different intensities: (a) TA color map with excitation pulse energy of 8 nJ; (b) TA color map with excitation pulse energy of 50 nJ; (c) evolution-associated difference spectrum (EADS) with excitation pulse energy of 8 nJ; (d) EADS with excitation pulse energy of 50 nJ.365 nm不同光强激发下的飞秒时间分辨瞬态吸收光谱　(a) 激发脉冲能量为8 nJ的瞬态吸收光谱彩图; (b) 激发脉冲能量为50 nJ的瞬态吸收光谱彩图; (c) 激发脉冲能量为8 nJ的演变相关差分光谱; (d) 激发脉冲能量为50 nJ的演变相关差分光谱

Fig. 3. Femtosecond time-resolved transient absorption (TA) spectra at 365 nm excitation with different intensities: (a) TA color map with excitation pulse energy of 100 nJ; (b) TA color map with excitation pulse energy of 500 nJ; (c) EADS with excitation pulse energy of 100 nJ; (d) EADS with excitation pulse energy of 500 nJ.365 nm不同光强激发下的飞秒时间分辨瞬态吸收光谱　(a) 激发脉冲能量为100 nJ的瞬态吸收光谱彩图; (b)激发脉冲能量为500 nJ的瞬态吸收光谱彩图; (c) 激发脉冲能量为100 nJ的演变相关差分光谱; (d)激发脉冲能量为500 nJ的演变相关差分光谱

Fig. 4. The kinetics of TA with different excitation intensities at exciton peaks: (a) 1P exciton bleach recovery (at 430 nm); (b) 2S exciton bleach recovery (at 468 nm); (c) 1S exciton bleach recovery (at 430 nm). All kinetic traces have been normalized to the same maximum amplitude.不同激发能量的瞬态吸收光谱数据在各个激子峰处的漂白动力学曲线　(a) 1P激子漂白峰(430 nm); (b) 2S激子漂白峰(468 nm); (c) 1S激子漂白峰(510 nm). 所有动力学曲线已经归一化至最大振幅

Fig. 5. Time-resolved photoluminescence color map.时间分辨荧光光谱图