Ultrafast carrier thermalization in lead iodide perovskite probed with two-dimensional electronic spectroscopy.

ABSTRACT: In band-like semiconductors, charge carriers form a thermal energy distribution rapidly after optical excitation. In hybrid perovskites, the cooling of such thermal carrier distributions occurs on timescales of about 300 fs via carrier-phonon scattering. However, the initial build-up of the thermal distribution proved difficult to resolve with pump-probe techniques due to the requirement of high resolution, both in time and pump energy. Here, we use two-dimensional electronic spectroscopy with sub-10 fs resolution to directly observe the carrier interactions that lead to a thermal carrier distribution. We find that thermalization occurs dominantly via carrier-carrier scattering under the investigated fluences and report the dependence of carrier scattering rates on excess energy and carrie

SUBMITTER: Richter JM 

PROVIDER: S-EPMC5575115 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature