Document Type
Article
Version
Final Published Version
Publication Title
Phys. Rev. Materials
Volume
6
Publication Date
2022
Abstract
Persistent photoresponses require optical excitations to metastable states, which are rare of ionic origin due to the indirect photon-ion interaction. In this work, we explore the photoinduced metastable proton states in the proton-transfer type molecular ferroelectric croconic acid. We observe that, after the photoexcitation, the changes of structural and ferroelectric properties relax in ∼10^3s, indicating persistent photoresponses of ionic origin. In contrast, the photoconductivity relaxes within 1 s. The 10^3s timescale suggests that the ionic metastable states result from proton transfer both along and out of the hydrogen bonds. This discovery unveils an ionic mechanism for the phototunability, which offers persistent opto-ferroelectric control for proton-transfer type molecular ferroelectrics.
Citation
Jiang, X., Wang, X., Buragohain, P., Clark, A. T., Lu, H., Poddar, S., Yu, L., DiChiara, A. D., Gruverman, A., Cheng, X. and X. Xu. 2022. "Persistent opto-ferroelectric responses in molecular ferroelectrics." Phys. Rev. Materials 6: 074412.
DOI
https://doi.org/10.1103/PhysRevMaterials.6.074412