文章基本信息

标题：Ferroelectric control of a Mott insulator
本地全文：下载
作者：Hiroyuki Yamada ; Maya Marinova ; Philippe Altuntas 等
期刊名称：Scientific Reports
电子版ISSN：2045-2322
出版年度：2013
卷号：3
DOI：10.1038/srep02834
出版社：Springer Nature
摘要：The electric field control of functional properties is an important goal in oxide-based electronics. To endow devices with memory, ferroelectric gating is interesting, but usually weak compared to volatile electrolyte gating. Here, we report a very large ferroelectric field-effect in perovskite heterostructures combining the Mott insulator CaMnO₃ and the ferroelectric BiFeO₃ in its “supertetragonal” phase. Upon polarization reversal of the BiFeO₃ gate, the CaMnO₃ channel resistance shows a fourfold variation around room temperature, and a tenfold change at ~200 K. This is accompanied by a carrier density modulation exceeding one order of magnitude. We have analyzed the results for various CaMnO₃ thicknesses and explain them by the electrostatic doping of the CaMnO₃ layer and the presence of a fixed dipole at the CaMnO₃/BiFeO₃ interface. Our results suggest the relevance of ferroelectric gates to control orbital- or spin-ordered phases, ubiquitous in Mott systems, and pave the way toward efficient Mott-tronics devices.