Improper Ferroelectric Polarisation in a Perovskite driven by Inter-site Charge Transfer and Ordering

التفاصيل البيبلوغرافية
العنوان: Improper Ferroelectric Polarisation in a Perovskite driven by Inter-site Charge Transfer and Ordering
المؤلفون: Chen, Wei-Tin, Wang, Chin-Wei, Wu, Hung-Cheng, Chou, Fang-Cheng, Yang, Hung-Duen, Simonov, Arkadiy, Senn, Mark S.
سنة النشر: 2018
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
الوصف: It is of great interest to design and make materials in which ferroelectric polarisation is coupled to other order parameters such as lattice, magnetic and electronic instabilities. Such materials will be invaluable in next-generation data storage devices. Recently, remarkable progress has been made in understanding improper ferroelectric coupling mechanisms that arise from lattice and magnetic instabilities. However, although theoretically predicted, a compact lattice coupling between electronic and ferroelectric (polar) instabilities has yet to be realised. Here we report detailed crystallographic studies of a novel perovskite Hg$^{\textbf{A}}$Mn$^{\textbf{A'}}_{3}$Mn$^{\textbf{B}}_{4}$O$_{12}$ that is found to exhibit a polar ground state on account of such couplings that arise from charge and orbital ordering on both the A' and B-sites, which are themselves driven by a highly unusual Mn$^{A'}$-Mn$^B$ inter-site charge transfer. The inherent coupling of polar, charge, orbital and hence magnetic degrees of freedom, make this a system of great fundamental interest, and demonstrating ferroelectric switching in this and a host of recently reported hybrid improper ferroelectrics remains a substantial challenge.
Comment: 9 pages, 7 figures
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevB.97.144102
URL الوصول: http://arxiv.org/abs/1803.05792
رقم الأكسشن: edsarx.1803.05792
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevB.97.144102