講演情報
[7p-N205-3][JSAP-Optica Joint Symposia Invited Talk] Imaging and control polarization switching in tetralayer graphene
Zhou Zhou1, Xiyao Peng1, Jianfeng Bi1, Fei Xue1, Jie Jiang1, Huizhen Wu1, Zhiwen Shi2, Haoliang Qian1, Toshikaze Kariyado3, 〇Sihan Zhao1 (1.Zhejiang University, 2.Shanghai Jiao Tong University, 3.National Institute for Materials Science)
キーワード：
graphene、2D sliding ferroelectricity、scanning near-field optical microscopy
Fundamentally distinct from the conventional ferroelectrics, the most discriminative hallmark of the emerging two-dimensional (2D) sliding ferroelectricity is the polarization switching via the domain wall (DW) sliding. Here, we report the first microscopic observation of the polarization switching phenomena in graphene-based systems [1], spatially resolved by a gate-tunable nanoscale optical imaging technique that is sensitive to electric polarization. We observe polarization switching occurs via electric-field triggered DW sliding between two adjacent domains featuring purely stacking-induced opposite electric polarizations in tetralayer graphene, thinnest natural graphene polytypes hosting broken inversion and mirror symmetries. The optical visualization of polarization switching and controlled switching by the electric field and mechanical manipulation demonstrate the sliding mechanism in 2D metals and open doors for optical studies of ferroelectricity and multiferroicity in graphene-based systems. If time allows, I will also briefly talk about our recent discovery of strongly hybridized phonons in one-dimensional van der Waals crystals [2].
[1] Z. Zhou, X. Peng et al., Optical imaging of spontaneous electric polarization and polarization switching in tetralayer graphene. Preprint arXiv:2504.06874 (2025)
[2] S. Sun et al., Strongly hybridized phonons in one-dimensional van der Waals crystals. Physical Review Letters 134, 176101 (2025)
[1] Z. Zhou, X. Peng et al., Optical imaging of spontaneous electric polarization and polarization switching in tetralayer graphene. Preprint arXiv:2504.06874 (2025)
[2] S. Sun et al., Strongly hybridized phonons in one-dimensional van der Waals crystals. Physical Review Letters 134, 176101 (2025)