発表者名 |
青木 俊太 |
指導教員名 |
岩佐 義宏 教授 |
発表題目(英語) |
Observation of the second harmonic generation in van der Waals antiferromagnet CuCrP2S6 |
要旨(英語) |
Two-dimensional magnet is attracting much attention as a new material platform for the search of novel magnetic properties. It shows the magnetic order even in few-layer samples [1,2], which can be thickness-dependent or modulated by applying the external field. Especially, in two-dimensional antiferromagnets, a variety of complex magnetic structures can be realized, thus offering unique magnetic properties and functionalities. However, since antiferromagnetic materials do not have net magnetization, it is generally difficult to observe the magnetic phase transition using magneto-optical Kerr effect or magnetic circular dichroism, which are frequently used for studying two-dimensional ferromagnets. Instead, second harmonic generation can be a good tool for studying the magnetism and resultant magnetic symmetries of two-dimensional antiferromagnet [3-6].
In this presentation, I will talk about the second harmonic generation in exfoliated flake samples of the van der Waals antiferromagnet CuCrP2S6. In the previous studies [7], it is reported that CuCrP2S6 shows a structural phase transition around 150 K from centrosymmetric to non-centrosymmetric crystal structure and an antiferromagnetic phase transition around 32 K. In the present study, we have successfully observed the second harmonic generation reflecting these structural and antiferromagnetic phase transitions. In my talk, the characteristic behaviors of the SHG signal and their origins will be also discussed.
[1] C. Gong *et al., Nature*, *546* 265(2017)
[2] B*. *Huang *et al., Nature*, *546* 270 (2017)
[3] Z. Sun *et al*., *Nature* *572*, 497 (2019)
[4] H. Chu *et al.,* *Phys. Rev. Lett.,* *124*, 027601 (2020)
[5] Z. Ni* et al., Nat. **Nanotech.*, *16* 782 (2021)
[6] K. Lee *et al.,* *Nano Lett. **21*, 3511 (2021)
[7] C. C. B. Park *et al.* *Adv. Electron. Mater.* 2101072 (2022) |
発表言語 |
日本語 |