PDF(Pubmed)
Abstract：
Dimensional modifications play a crucial role in various applications, especially in the context of device miniaturization, giving rise to novel quantum phenomena. The many-body dynamics induced by dimensional modifications, including electron-electron, electron-phonon, electron-magnon and electron-plasmon coupling, are known to significantly affect the atomic and electronic properties of the materials. By reducing the dimensionality of orthorhombic CoSe2 and forming heterostructure with bilayer graphene using molecular beam epitaxy, we unveil the emergence of two types of phase transitions through angle-resolved photoemission spectroscopy and scanning tunneling microscopy measurements. We disclose that the 2 × 1 superstructure is associated with charge density wave induced by Fermi surface nesting, characterized by a transition temperature of 340 K. Additionally, another phase transition at temperature of 160 K based on temperature dependent gap evolution are observed with renormalized electronic structure induced by electron-boson coupling. These discoveries of the electronic and atomic modifications, influenced by electron-electron and electron-boson interactions, underscore that many-body physics play significant roles in understanding low-dimensional properties of non-van der Waals Co-chalcogenides and related heterostructures.
摘要：
尺寸修改在各种应用中起着至关重要的作用，特别是在设备小型化的背景下，产生了新的量子现象。由尺寸修改引起的多体动力学，包括电子-电子，电子-声子，电子-磁振子和电子-等离子体激元耦合，已知显著影响材料的原子和电子性质。通过降低正交CoSe2的维数并使用分子束外延与双层石墨烯形成异质结构，我们通过角度分辨光发射光谱和扫描隧道显微镜测量揭示了两种相变的出现。我们公开了2×1的超结构与费米表面嵌套引起的电荷密度波有关，其特征在于340K的转变温度。此外，观察到基于温度依赖性间隙演化的160K温度下的另一个相变，并通过电子-玻色子耦合引起了重新归一化的电子结构。这些电子和原子修饰的发现，受电子-电子和电子-玻色子相互作用的影响，强调多体物理学在理解非范德瓦尔斯钴硫族化合物和相关异质结构的低维性质中起着重要作用。
