Fig. 3: Ultrafast (<100 fs) charge transfer between hemes in nanowires revealed by femtosecond transient absorption spectroscopy (fs-TA).

a Schematic of fs-TA. A pump beam (λ = 545 nm) excites a nanowire sample and is followed by a probe beam after a time delay. The differential absorption between the initial and time-delayed spectra is detected and reported as optical density. b Averaged transient absorption data of nanowires (n = 6 independent experiments) where colours represent the milli optical density (mOD). c Normalized change in differential absorption with wavelength at different delay times. Key wavelengths are marked as λ = 410 nm (green), λ = 424 nm (red), and λ = 367 nm (blue). d The experimental (solid) and simulated (dashed) spectra of oxidized, reduced, and singlet doubly-oxidized nanowires. Wavelength markers are same as in Fig. 3c. e Normalized change in differential absorption over delay time at key wavelengths. Time-markers are shown in the same colour as time traces in Fig. 3c. Traces in c and e represent mean of n = 6 independent experiments. Source data are provided as a Source Data file.