2018/12/19 by Yang Lan, Lan, Yang, Benjamin J. Dringoli +13
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Optical properties and cooling technologies in crystalline materials #Perovskite Materials and Applications #Solid-state spectroscopy and crystallography
paper · pdf · doi:10.48550/arxiv.1812.07752
openalex publication_date 2018/12/19 · openalex created_date 2019/06/27 · openalex updated_date 2026/07/28
Hybrid organic-inorganic halide perovskites have shown remarkable optoelectronic properties (1-3), believed to originate from correlated motion of charge carriers and the polar lattice forming large polarons (4-7). Few experimental techniques are capable of probing these correlations directly, requiring simultaneous sub-meV energy and femtosecond temporal resolution after absorption of a photon (8). Here we use transient multi-THz spectroscopy, sensitive to the internal motions of charges within the polaron, to temporally and energetically resolve the coherent coupling of charges to longitudinal optical phonons in single crystal CH3NH3PbI3 (MAPI). We observe room temperature quantum beats arising from the coherent displacement of charge from the coupled phonon cloud. Our measurements provide unambiguous evidence of the existence of polarons in MAPI.