Professor of Physics Xuemei M. Cheng and Alums Co-Author Article, July 2022
Persistent Opto-Ferroelectric Responses in Molecular Ferroelectrics
Authors: Xuanyuan Jiang; Xiao Wang, Ph.D. '20; Pratyush Buragohain; Andy T. Clark, Ph.D. '22; Haidong Lu, Shashi Poddar, Le Yu, Anthony D. DiChiara, Alexei Gruverman, Xuemei Cheng, and Xiaoshan Xu
Source: Physical Review Materials, Volume: 6, Issue: 7, DOI: 10.1103/PhysRevMaterials.6.074412, July 2022
Type of Publication: Journal Article
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 similar to 103 s, indicating persistent photoresponses of ionic origin. In contrast, the photoconductivity relaxes within 1 s. The 103 s 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.
Xuemei M. Cheng is dean of graduate studies and professor of physics.