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Updated: Apr 6, 2026
08:12
Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
10.2K
Two-Photon Absorption in Organometallic Bromide Perovskites
Grant Walters1, Brandon R Sutherland1, Sjoerd Hoogland1
1Department of Electrical and Computer Engineering, University of Toronto , Toronto, Ontario M5S 3G4, Canada.
ACS Nano
|July 22, 2015
Summary
Organometallic trihalide perovskites exhibit two-photon absorption, enabling their use in ultrafast photonics. Researchers quantified this nonlinear absorption in single crystals, demonstrating their potential as low-cost photodetectors.
Area of Science:
- Materials Science
- Optoelectronics
- Quantum Optics
Background:
- Organometallic trihalide perovskites are solution-processed semiconductors with applications in optoelectronics.
- Recent advances allow synthesis of large, high-purity single crystals.
- These crystals offer a unique platform for studying nonlinear optical phenomena.
Purpose of the Study:
- To investigate and quantify two-photon absorption in organometallic trihalide perovskite single crystals.
- To explore the potential of these perovskites as nonlinear absorbers in ultrafast photonics.
Main Methods:
- Synthesis of large, high-purity methylammonium lead bromide (CH3NH3PbBr3) single crystals.
- Pumping crystals with intense 800 nm light to observe photoluminescence.
- Measurement of the nonlinear absorption coefficient.
- Fabrication of a two-photon perovskite photodetector for laser autocorrelation.
Main Results:
- Observation of band-to-band photoluminescence at 572 nm upon 800 nm excitation, confirming two-photon absorption.
- Determination of the nonlinear absorption coefficient of CH3NH3PbBr3 to be 8.6 cm GW(-1).
- Successful electrical autocorrelation of a 100 fs pulsed laser using the perovskite photodetector.
Conclusions:
- Organometallic trihalide perovskites exhibit significant two-photon absorption properties.
- These materials are viable, low-cost nonlinear absorbers for ultrafast photonics applications.
- Perovskite single crystals provide a robust platform for fundamental optical studies and device development.
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