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Dion-Jacobson Perovskites with a Ferroelectrically Switchable Chiral Nonlinear Optical Response
Weixin He1,2, Changjiang Chen3, Shiyao Wu4
1Department of Chemistry, National University of Singapore, Singapore 117543, Singapore.
Journal of the American Chemical Society
|December 19, 2024
Summary
Researchers demonstrated electrically switchable second harmonic generation circular dichroism in chiral ferroelectric perovskites. This breakthrough enables secure optical communications and advanced optical logic devices.
Area of Science:
- Materials Science
- Optoelectronics
- Crystallography
Background:
- Electrically switchable second harmonic generation (SHG) is crucial for electro-optic modulators in data communication and quantum optics.
- Coupling circular dichroism (CD) with electrically controlled SHG offers enhanced bandwidth, security, and multiple modulation modes for optical logic.
- Ferroelectrically switchable chiral second-order nonlinearity is a rarely reported phenomenon.
Purpose of the Study:
- To demonstrate electro-optic modulation of SHG using the multipolar effect in a novel chiral ferroelectric material.
- To investigate the ferroelectric switching of SHG circular dichroism (SHG-CD) in a stable two-dimensional hybrid perovskite.
- To explore the potential of electrically controlled SHG-CD for applications in encrypted optical communications.
Main Methods:
- Synthesis and characterization of air-stable chiral ferroelectric two-dimensional hybrid perovskite crystals: s-(FBDA)CdCl4 (s-FCC).
- Investigation of the second harmonic generation (SHG) response and its circular dichroism (CD) properties.
- Analysis of the ferroelectric switching behavior and its effect on SHG-CD through multipolar moment reconfiguration.
Main Results:
- Demonstrated ferroelectric switching of SHG-CD in s-FCC crystals, a stable material.
- Observed a π/2 circular difference in SHG due to the reconfiguration of chirality-induced multipolar moments.
- Showcased the reversal of circularly polarized light sensitivity upon ferroelectric switching.
- Confirmed the potential for encrypted optical communication transmission using electrically controlled SHG-CD.
Conclusions:
- Chiral ferroelectric perovskites exhibit ferroelectrically switchable SHG-CD.
- The multipolar effect in s-FCC enables electrical control over SHG-CD.
- This phenomenon holds promise for advanced applications in secure optical communications and optical logic devices.
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