在磁弹性超级格子中的谷区选择性子-子散射
Liyang Liao1, Jorge Puebla2, Kei Yamamoto2,3
1Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan.
Physical review letters
|November 13, 2023
概括
我们在磁弹性超级格子中演示了谷选择性的声子-马格农散射,使磁场能够控制声子传输. 这项研究为利用合的磁-声相互作用来操纵山谷声行为铺平了道路.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 声学 声学 在声学方面
背景情况:
- 声子和磁子是准粒子,可以被设计成周期性结构,如声子和磁子晶体.
- 对声子和磁子的联合研究为新型传输现象提供了潜力,例如由磁场调节的山谷声子传输.
- 磁弹性超级网格为研究磁性和声学特性之间的相互作用提供了一个平台.
研究的目的:
- 为了证明和研究在磁弹性超级格子中谷区选择性的声子 - 磁子散射.
- 探索格子对称性和磁化在控制非互惠声传输中的作用.
- 建立一种方法,通过可调节的磁-声联接来操纵山谷声传输.
主要方法:
- 使用非互惠的表面声波传输测量.
- 制造和表征磁弹性超级网格.
- 分析声波带结构及其与传输光谱的关系.
主要成果:
- 证明了谷选择性的声子 - 磁子散射,导致非互惠的表面声波传输.
- 表明格子对称性和外平面磁化控制非互惠的标志.
- 在音声传输间隙附近观察到非互惠性峰值,与理论预测一致.
- 确定了山谷声子在诱导与磁子结合的循环极化菌株中的关键作用.
结论:
- 谷声子-马格农散射是一种实现非互惠声子传输的可行机制.
- 通过磁场和格子对称性来证明对非互惠性的控制,为自旋电子和声学设备开辟了道路.
- 这项工作为未来的研究提供了基础,通过工程性磁 - 声相互作用来操纵声传输.
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