Strongly bound excitons in Ruddlesden-Popper 2D perovskites

ORAL

Abstract

Ruddlesden-Popper halide perovskites are 2D solution-processed quantum wells with a general formula A2A’n-1MnX3n+1, where A, A’ are cations, M is a metal, X is a halide, and their physical properties can be tuned by varying the perovskite layer thickness (n value). They have recently emerged as efficient semiconductors for optoelectronics [1-3]. However, fundamental questions concerning the nature of optical resonances, their scaling with quantum well thickness, and the physics behind the exciton properties, remain unresolved. Here, using optical spectroscopy and 60-Tesla magneto-absorption supported by modelling, we unambiguously demonstrate that the optical resonances arise from tightly bound excitons with binding energies varying from 470 meV to 125 meV with increasing thickness from n=1 to 5 [4]. Comprehensive modelling of exciton states enable the understanding of dielectric confinement effects which prevail over quantum confinement in 2D perovskites. From these results we produce a general scaling behaviour for the binding energy of exciton states in Ruddlesden-Popper perovskites.

[1] Tsai et al., Nature (2016), 536, 312-316.
[2] M. Yuan et al., Nat. Nanotechnol. (2016), 11, 872-877.
[3] Blancon et al., Science (2017), 355, 1288-1292.
[4] Blancon et al., arXiv:1710.07653.

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Presenters

  • Jean-Christophe Blancon

    • Los Alamos National Laboratory
    • Materials Physics and Applications Division, Los Alamos National Laboratory

Authors

  • Jean-Christophe Blancon

    • Los Alamos National Laboratory
    • Materials Physics and Applications Division, Los Alamos National Laboratory

  • Andreas Steir

    • Los Alamos National Laboratory

  • Wanyi Nie

    • Los Alamos National Laboratory
    • Los Alamos National Lab
    • Materials Physics and Applications Division, Los Alamos National Laboratory

  • Hsinhan Tsai

    • Rice University
    • Los Alamos National Lab

  • Constantinos Stoumpos

    • Northwestern University

  • Scott Crooker

    • National High Magnetic Field Laboratory, Los Alamos National Laboratory
    • National High Magnetic Field Laboratory, Los Alamos National Lab
    • Los Alamos National Laboratory
    • NHMFL, Los Alamos National Laboratory

  • Mercouri Kanatzidis

    • Department of Chemistry, Northwestern University
    • Materials Science Division, Argonne National Laboratory
    • Northwestern Univ
    • Materials Science Division, Argonne Natl Lab
    • Northwestern University

  • Jared Crochet

    • Los Alamos National Laboratory

  • Jacky Even

    • INSA FOTON
    • INSA de Rennes
    • Université de Rennes 1
    • Fonctions Optiques pour les Technologies de l’Information (FOTON), Institut National des Sciences Appliquées (INSA) de Rennes, CNRS, UMR 6082

  • Aditya Mohite

    • MPA-11: Materials Synthesis and Integrated Devices, Los Alamos National Laboratory
    • Los Alamos National Laboratory
    • Los Alamos National Lab
    • Materials Physics and Applications Division, Los Alamos National Laboratory