Electromagnon by chiral spin dynamics in the triangular lattice antiferromanet
Electromagnon by chiral spin dynamics in the triangular lattice antiferromanet
复制标题
三角晶格反铁磁体中手性自旋动力学的电磁子
DOI：
10.1103/physrevb.90.060413
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
and K. Watanab
中科院分区：
文献类型：
--
作者：
S. Kimura;T. Fujita;M. Hagiwara;H. Yamaguchi;T. Kashiwagi;N. Tearada;Y. Sawada;and K. Watanab
从偏振光照射下的高场电子自旋共振测量中，我们揭示了电磁振子的存在，即，磁振子激发振荡电场的光，在场诱导的1/5平台阶段的三角晶格反铁磁体。我们指出，在三角晶格上具有共线自旋结构的磁有序相中，出现了使矢量自旋手征在波矢处均匀涨落的奇异磁振子模。我们的实验结果表明，这种磁振子模式与光的电分量耦合，导致电磁振子的出现。此外，在圆偏振光的测量表现出异常的行为，圆二色性，这是通常发现在磁共振，是缺乏在共振信号的电磁振子。本文还讨论了电磁振子的微观机理。
From high field electron spin resonance measurements in illuminating polarized light, we have revealed the existence of electromagnon, i.e., magnon excitation by oscillatory electric fields of light, in the field-induced 1/5-plateau phase of the triangular lattice antiferromagnet. We indicate that peculiar magnon modes, which generate uniform fluctuation of the vector spin chirality at wave vector, appear in the magnetic ordered phase with a collinear spin structure on triangular lattice. Our experimental results demonstrate that such magnon modes couple with an electric component of light, leading to the emergence of the electromagnon. Moreover, the measurements in circularly polarized light exhibit an anomalous behavior that circular dichroism, which is usually found in magnetic resonance, is absent in the resonance signal of the electromagnon. The microscopic mechanism of the electromagnon inis also discussed.