Testing the fate of nascent holes in CdSe nanocrystals with sub-10 fs pump-probe spectroscopy

Numerous studies have reported that transient absorption spectra in core CdSe nanocrystals do not register state filling in 1S h , an absence which has profound consequences in light-emitting applications. It has been assigned alternatively to rapid hole trapping, or to distribution over a dense degenerate valence band manifold which includes dark states. Here we attempt to observe early contributions of nascent holes to the bleaching of the band edge exciton transition by conducting 1S e 1S h pump-1S e 1S h probe spectroscopy with