Campus Units

Chemistry, Electrical and Computer Engineering, Physics and Astronomy, Ames Laboratory, Microelectronics Research Center (MRC)

Document Type

Article

Publication Version

Accepted Manuscript

Publication Date

7-9-2018

Journal or Book Title

MRS Communications

DOI

10.1557/mrc.2018.114

Abstract

Using time-resolved laser-scanning confocal microscopy and ultrafast optical pump/THz probe spectroscopy, we measure photoluminescence and THz-conductivity in perovskite micro-crystals and films. Photoluminescence quenching and lifetime variations occur from local heterogeneity. Ultrafast THz-spectra measure sharp quantum transitions from excitonic Rydberg states, providing weakly bound excitons with a binding energy of ~13.5 meV at low temperatures. Ab-initio electronic structure calculations give a direct band gap of 1.64 eV, a dielectric constant ~18, heavy electrons, and light holes, resulting in weakly bound excitons, consistent with the binding energies from experiment. The complementary spectroscopy and simulations reveal fundamental insights into perovskite light-matter interactions.

Comments

This is a manuscript of an article published as Liu, Zhaoyu, K. C. Bhamu, Liang Luo, Satvik Shah, Joong-Mok Park, Di Cheng, Men Long, Rana Biswas, F. Fungara, Ruth Shinar, Joseph Shinar, Javier Vela, and Jigang Wang. "Spatial–temporal spectroscopy characterizations and electronic structure of methylammonium perovskites." MRS Communications (2018). doi: 10.1557/mrc.2018.114. Posted with permission.

Copyright Owner

Materials Research Society

Language

en

File Format

application/pdf

Available for download on Wednesday, January 09, 2019

Published Version

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