The ultrafast pump-probe microscope has been utilized to spatially map the ultrafast dynamics of photoexcited carriers and phonons in InSb with varied carrier concentrations. In this study, the negative and positive components of transient reflectivity-change spectra (ΔR/R) are associated with the dynamics of photoexcited holes and phonons, respectively. The mapping of phonon morphology (i.e. positive ΔR/R on a ps-ns timescale) shows the delocalized electron-phonon coupling in InSb, especially for large carrier concentrations. In contrast, the recombination of electrons and holes is rather localized inside the pumped spot. According to morphological analyses of oscillatory signals in ΔR/R, we found that an electric field applied to InSb can further manipulate the phonon strength and lifetime. For the case of large carrier concentrations, the spatial breadth of phonons has been first observed in InSb.

超快泵浦探针显微镜已被用于空间映射具有不同载流子浓度的 InSb 中光激发载流子和声子的超快动力学。在这项研究中，瞬态反射率变化光谱 (Δ R / R )的负分量和正分量分别与光激发空穴和声子的动力学有关。声子形态的映射（即ps-ns 时间尺度上的正 Δ R / R）显示了 InSb 中的离域电子 - 声子耦合，特别是对于大载流子浓度。相比之下，电子和空穴的复合更集中在泵浦点内部。根据 Δ R / R中振荡信号的形态分析，我们发现施加到 InSb 的电场可以进一步操纵声子强度和寿命。对于大载流子浓度的情况，声子的空间宽度首先在 InSb 中观察到。