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Updated: Sep 8, 2025
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Tunable chiroptical activity and second-harmonic generation in chiral one-dimensional perovskites
Zhihang Guo1, Xin Qiu2, Tingchao He2
1State Key Laboratory of Photonics and Communications, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China. cswang@sjtu.edu.cn.
Chemical Communications (Cambridge, England)
|August 19, 2025
Summary
Researchers tuned chiral perovskite properties by adjusting lead iodide levels, enhancing chiroptical activity and achieving effective second-harmonic generation. This work opens new avenues for chiral optoelectronics.
Area of Science:
- Materials Science
- Optoelectronics
- Solid-State Chemistry
Background:
- Chiral perovskites are promising materials for advanced optical applications.
- Controlling their chiroptical activity and nonlinear optical properties is crucial for device development.
Purpose of the Study:
- To investigate the effect of lead iodide proportion on the chiroptical activity of chiral one-dimensional perovskites.
- To achieve and characterize second-harmonic generation (SHG) in these tailored chiral perovskite thin films.
Main Methods:
- Synthesis of chiral perovskite thin films with varying lead iodide concentrations.
- Characterization of chiroptical activity using circular dichroism (CD) spectroscopy.
- Measurement of nonlinear optical properties, specifically second-harmonic generation.
Main Results:
- Significant modulation of intrinsic chiroptical activity by tuning lead iodide proportion.
- Achieved a circular dichroism dissymmetry factor (g_CD) of up to 0.11.
- Demonstrated effective second-harmonic generation and observed pronounced second-order nonlinear chiroptical responses in chiral perovskite thin films.
Conclusions:
- Lead iodide proportion is a key factor in controlling the chiroptical and nonlinear optical properties of chiral perovskites.
- The developed chiral perovskite thin films show potential for applications in nonlinear optics and chiroptical devices.
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