Femtosecond pump-broadband probe study of primary doped polyaniline – The evidence of neutral primary photoexcitations

Ultrafast Spin-Resolved Spectroscopy Reveals Dominant Exciton Dynamics in Conducting Polymer Polyaniline

“…This is because slight changes in sample environments, such as sample type (film or solution) or differences during sample preparation, contribute to large fluctuations in time-domain signals due to the large dielectric mismatch. Previous studies have reported substantially different dynamics in time-resolved transient signals within a few picoseconds, and the results appeared to show inconsistent sample dependence. , …”

“…Previous studies have reported substantially different dynamics in time-resolved transient signals within a few picoseconds, and the results appeared to show inconsistent sample dependence. 16,17 To overcome this problem, ultrafast spin-resolved pump-probe spectroscopy was employed.…”

“…Previous studies have reported substantially different dynamics in time-resolved transient signals within a few picoseconds, and the results appeared to show inconsistent sample dependence. 16,17 To overcome this problem, ultrafast spin-resolved pump− probe spectroscopy was employed. The spin-resolved spectroscopy has been widely used in semiconductor physics to investigate spin relaxation dynamics of the excited charge carriers.…”

“…Conversely, a recent investigation 17 has suggested that carrier relaxation is dominated by excitons. When an optical pulse creates electron and hole (e-h) pairs, strong Coulomb interactions lead to the formation of bound e-h pairs known as molecular excitons (Figure 2c).…”

Femtosecond spectroscopy of promising materials

“…[26], a metal state with a half-filled conduction band. 3) revealed that the dynamics of the 750-nm band are related to excitons; the longer-wavelength part reflects the appearance of charge carriers, but the main changes in the difference spectrum are related to electric fields [28]. The difference spectra exhibited three distinct features: the bleaching of the 750-nm band and photoinduced absorption with the center at 460 nm and in the wavelength range from 850 to 1050 nm [27] (Fig.…”