Polarization switching induced by domain wall sliding in two-dimensional ferroelectric monochalcogenides

التفاصيل البيبلوغرافية
العنوان: Polarization switching induced by domain wall sliding in two-dimensional ferroelectric monochalcogenides
المؤلفون: Petralanda, Urko, Olsen, Thomas
المصدر: 2D Materials 10, 015001 (2023)
سنة النشر: 2022
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics
الوصف: The ability to switch between distinct states of polarization comprises the defining property of ferroelectrics. However, the microscopic mechanism responsible for switching is not well understood and theoretical estimates based on coherent monodomain switching typically overestimate experimentally determined coercive fields by orders of magnitude. In this work we present a detailed first principles characterization of domain walls (DWs) in two-dimensional ferroelectric GeS, GeSe, SnS and SnSe. In particular, we calculate the formation energies and migration barriers for 180 and 90 DWs, and then derive a general expression for the coercive field assuming that polarization switching is mediated by DW migration. We apply our approach to the materials studied and obtain good agreement with experimental coercive fields. The calculated coercive fields are up to two orders of magnitude smaller than those predicted from coherent monodomain switching in GeSe, SnS and SnSe. Finally, we study the optical properties of the compounds and find that the presence of 180 DWs leads to a significant red shift of the absorption spectrum, implying that the density of DWs may be determined by means of simple optical probes.
Comment: 14 pages, 6 figures
نوع الوثيقة: Working Paper
DOI: 10.1088/2053-1583/ac94e0
URL الوصول: http://arxiv.org/abs/2204.12209
رقم الأكسشن: edsarx.2204.12209
قاعدة البيانات: arXiv
الوصف
DOI:10.1088/2053-1583/ac94e0