title: Two-Photon Absorption in Organometallic Bromide Perovskites.
abstract: Organometallic trihalide perovskites are solution-processed semiconductors that have made great strides in third-generation thin film light-harvesting and light-emitting optoelectronic devices. Recently, it has been demonstrated that large, high-purity single crystals of these perovskites can be synthesized from the solution phase. These crystals' large dimensions, clean bandgap, and solid-state order have provided us with a suitable medium to observe and quantify two-photon absorption in perovskites. When CH3NH3PbBr3 single crystals are pumped with intense 800 nm light, we observe band-to-band photoluminescence at 572 nm, indicative of two-photon absorption. We report the nonlinear absorption coefficient of CH3NH3PbBr3 perovskites to be 8.6 cm GW(-1) at 800 nm, comparable to epitaxial single-crystal semiconductors of similar bandgap. We have leveraged this nonlinear process to electrically autocorrelate a 100 fs pulsed laser using a two-photon perovskite photodetector. This work demonstrates the viability of organometallic trihalide perovskites as a convenient and low-cost nonlinear absorber for applications in ultrafast photonics.
authors.affiliation: Department of Electrical and Computer Engineering, University of Toronto , Toronto, Ontario M5S 3G4, Canada.
authors.forename: Grant
authors.initials: G
authors.lastname: Walters
authors.affiliation: Department of Electrical and Computer Engineering, University of Toronto , Toronto, Ontario M5S 3G4, Canada.
authors.forename: Brandon R
authors.initials: BR
authors.lastname: Sutherland
authors.affiliation: Department of Electrical and Computer Engineering, University of Toronto , Toronto, Ontario M5S 3G4, Canada.
authors.forename: Sjoerd
authors.initials: S
authors.lastname: Hoogland
authors.affiliation: Division of Physical Sciences and Engineering, Solar and Photovoltaics Engineering Research Center, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Dong
authors.initials: D
authors.lastname: Shi
authors.affiliation: Department of Electrical and Computer Engineering, University of Toronto , Toronto, Ontario M5S 3G4, Canada.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Comin
authors.affiliation: Department of Electrical and Computer Engineering, University of Toronto , Toronto, Ontario M5S 3G4, Canada.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Sellan
authors.affiliation: Division of Physical Sciences and Engineering, Solar and Photovoltaics Engineering Research Center, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Osman M
authors.initials: OM
authors.lastname: Bakr
authors.affiliation: Department of Electrical and Computer Engineering, University of Toronto , Toronto, Ontario M5S 3G4, Canada.
authors.forename: Edward H
authors.initials: EH
authors.lastname: Sargent
keywords: CH3NH3PbBr3; autocorrelator; perovskite; photoconductor; two-photon absorption