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Revisiting the Optical Response of Two-Dimensional Perovskites: Beyond Excitons
Alessandro Surrente1, Mateusz Dyksik1, Paulina Plochocka1,2
1Department of Experimental Physics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, Wrocław 50-370, Poland.
Nano Letters
|June 19, 2026
Summary
Two-dimensional Ruddlesden-Popper perovskites have complex optical properties due to electronic, vibrational, and photonic interactions. This review unifies their interpretation by examining exciton behavior and light interactions in these 2D materials.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Optoelectronics
Background:
- Two-dimensional (2D) Ruddlesden-Popper metal halide perovskites display unique optical characteristics, including sidebands, quasi-plateaus, and thickness-dependent spectral features.
- Understanding these optical properties is crucial for their application in optoelectronic devices.
Purpose of the Study:
- To reassess the optical properties of 2D Ruddlesden-Popper perovskites.
- To provide a unified framework for interpreting their optical spectra by considering electronic, vibrational, and photonic effects.
Main Methods:
- Examining the interplay between electronic structure, exciton fine structure, exciton-phonon coupling, and photonic effects.
- Analyzing reflection, transmission, and absorption spectra.
- Investigating photoluminescence response, including exciton-polaron formation and defect-assisted recombination.
Main Results:
- High excitonic oscillator strength and refractive index lead to excitonic stop bands and interference effects dominating spectra.
- Photoluminescence response is complex, showing evidence of exciton-polaron formation, self-trapping, and defect-assisted recombination.
- A unified framework is established by considering electronic, vibrational, and photonic effects equally.
Conclusions:
- The rich optical response of 2D perovskites arises from a combination of electronic, vibrational, and photonic phenomena.
- This work offers a comprehensive approach to understanding and predicting optical spectra in these materials.
- The findings are vital for advancing the design and application of 2D perovskite-based technologies.
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