Pronounced orbital-selective electron-electron correlation and electron-phonon coupling in V2Se2O
Mingzhe Hu, Ziyin Song, Jingwen Cheng, Gexing Qu, Zhanghuan Li, Yu Huang, Jundong Zhu, Guangyu Zhang, Dacheng Tian, Lan Chen, Zhijun Tu, Hechang Lei, Xiaoping Ma, Huaixin Yang, Zhongxu Wei, Genfu Chen, Hongming Weng, Tian Qian, Hang Li
Published: 2025/10/6
Abstract
Orbital-selective many-body effects, in which electrons occupying different orbitals experience distinct interaction strengths, play a crucial role in correlated multiorbital materials. However, these effects usually manifest in a complex manner, obscuring their microscopic origins. Here, by combining angle-resolved photoemission spectroscopy measurements with theoretical calculations, we reveal pronounced orbital selectivity in both electron-electron correlation and electron-phonon coupling in the van der Waals material V2Se2O. Electron correlation induces distinct bandwidth renormalization exclusively in the V d_xy-derived band, while the bands mainly composed of the other d orbitals remain essentially unrenormalized. Orbital-resolved analyses identify that the filling number and the bandwidth are decisive factors governing orbital-dependent correlation. Simultaneously, the d_(xz/yz)-derived band exhibits a sharp kink anomaly, arising from enhanced coupling to high-energy phonon modes dominated by oxygen vibrations. Such pronounced orbital selectivity positions V2Se2O as a rare and prototypical platform for unravelling the microscopic mechanisms of orbital-selective electron-electron and electron-phonon interactions, and offers guiding principles for the design of correlated multiorbital materials.