PbMg1/3Nb2/3O3在结温度区域中发生过电衰老
S B Vakhrushev1, E Yu Koroleva1, A Yu Molokov1
1Peter the Great St. Petersburg Polytechnic University, Polytechnicheskaya 29, St.-Petersburg 195251, Russia.
Journal of physics. Condensed matter : an Institute of Physics journal
|November 23, 2023
概括
在基酸 (Pb(Mg1/3Nb2/3) O3) 放松剂中研究了结温度周围的衰老. 新的数据揭示了多极纳米区域所产生的结以上的衰老效应,为放松者行为提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 介电光谱学 介电光谱学
背景情况:
- 放松铁电,特别是Pb(Mg1/3Nb2/3) O3,表现出复杂的衰老现象.
- 之前的研究主要集中在低温,类似玻璃的行为,留下了一个关于结温度的理解差距.
研究的目的:
- 系统地研究Pb(Mg1/3Nb2/3) O3在其结温度 (Tf ≈ 240 K) 周围的介电光谱的演变.
- 在一个广泛的频率范围 (10-1 Hz到106 Hz) 中,在结点以下和上面描述衰老效应.
主要方法:
- 对Pb{Mg1/3Nb2/3) O3.3.进行了介电光谱测量.
- 数据分析涵盖了从10−1 Hz到106 Hz的频率,无论是Tf以下还是Tf以上.
- 研究了介电光谱的依赖时间的变化,以观察衰老.
主要成果:
- 确认等待时间-频率缩放低于Tf (≈50 Hz),在更高频率的偏差可能是由于复杂的放松实体.
- 在有限的频率范围内,在介电损失峰值以下,观察到Tf以上的衰老效应.
- 老化表现为介电损失光谱的硬化和缩小以及随着时间的推移而降低的介电强度.
结论:
- 高于Tf的衰老与跨越多个化学有序区域的退化的极性纳米区域 (多PNR) 的形成有关.
- 这些多个PNR比单个区域的PNR大,它们的结有助于观察到的光谱变化.
- 这项研究提供了关键的数据放松或衰老的动态在结过渡附近.
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