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Spin and valley degrees of freedom in materials without inversion symmetry promise previously unknown device functionalities, such as spin-valleytronics. Control of material symmetry with electric fields (ferroelectricity), while breaking additional symmetries, including mirror symmetry, could yield phenomena where chirality, spin, valley, and crystal potential are strongly coupled. Here we report the synthesis of a halide perovskite semiconductor that is simultaneously photoferroelectricity switchable and chiral. Spectroscopic and structural analysis, and first-principles calculations, determine the material to be a previously unknown low-dimensional hybrid perovskite (R)-(−)-1-cyclohexylethylammonium/(S)-(+)-1 cyclohexylethylammonium) PbI 3 . Optical and electrical measurements characterize its semiconducting, ferroelectric, switchable pyroelectricity and switchable photoferroelectric properties. Temperature dependent structural, dielectric and transport measurements reveal a ferroelectric-paraelectric phase transition. Circular dichroism spectroscopy confirms its chirality. The development of a material with such a combination of these properties will facilitate the exploration of phenomena such as electric field and chiral enantiomer–dependent Rashba-Dresselhaus splitting and circular photogalvanic effects.
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This content will become publicly available on March 7, 2026
Chiral Assemblies of π-Conjugated Molecules: Fundamentals, Processing Strategies, and Applications in (Opto)Electronics
Chirality, a fundamental attribute of asymmetry, pervades in both nature and functional soft materials. In chiral material systems design, achieving global symmetry breaking of building blocks during assembly, with or without the aid of additives, has emerged as a promising strategy across domains including chiral sensing, electronics, photonics, spintronics, and biomimetics. We first introduce the fundamental aspects of chirality, including its structural basis and symmetry-breaking mechanisms considering free energy minimization. We particularly emphasize supramolecular assembly, such as through the formation of chiral liquid crystal phases. Next, we summarize processing strategies to control chiral symmetry breaking, exploiting external fields such as flow, magnetic fields, and templates. The final section discusses interactions between chiral molecular assemblies with circularly polarized (CP) light and electronic spin and their applications in CP light detectors, CP-spin-organic light-emitting diodes, CP displays, and spintronic devices based on the chirality-induced spin selectivity effect.
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- Award ID(s):
- 1847828
- PAR ID:
- 10599082
- Publisher / Repository:
- Annual Reviews
- Date Published:
- Journal Name:
- Annual Review of Chemical and Biomolecular Engineering
- ISSN:
- 1947-5438
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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