Ultrahigh anharmonicity low-permittivity tunable nanocrystalline thin-film BaTi2O5
Ultrahigh anharmonicity low-permittivity tunable nanocrystalline thin-film BaTi2O5
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DOI：
10.1016/j.actamat.2021.116712
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发表时间：
2021-03-05
期刊：
影响因子：
9.4
通讯作者：
Spanier, Jonathan E.
中科院分区：
文献类型：
--
作者：
Falmbigl, Matthias;Golovina, Iryna S.;Spanier, Jonathan E.
有源电路和系统中的电可调谐介质薄膜受到电容诱导延迟和阻抗匹配的挑战，需要较低的介电常数。本文提出了一种通过考虑八面体之间不同连接性的影响来提高含TiO6八面体化合物的本征可调性的方法。这种在纳米晶BaTi2O5薄膜中的连接性变体使得钛的非谐相互作用增加了两个数量级，从而在不牺牲可调谐性的情况下使室温下的介电常数下降了约65%至70。与钙钛矿结构(类似于4埃)相比，共边TiO6八面体具有更短的Ti-Ti距离，仅为2.91埃，允许较大的场诱导结构重排和本征可调谐。(C)2021 Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
Electrically tunable dielectric thin films in active circuits and systems are challenged by capacitance-induced delays and impedance matching requiring a lower dielectric constant. Here an approach to increasing the intrinsic tunability of compounds containing TiO6 octahedra by considering the influence of different connectivity among these octahedra is presented. Such connectivity variants in nanocrystalline monoclinic BaTi2O5 thin films enable a two orders of magnitude enhancement in Ti anharmonic interaction, thereby permitting a approximate to 65% decrease in dielectric constant to 70 at room temperature without sacrificing tunability. Edge-sharing TiO6 octahedra possess a much shorter Ti-Ti distance of only 2.91 angstrom as compared to the perovskite structure (similar to 4 angstrom), permitting large field-induced structural re-arrangement and intrinsic tunability. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.