Real-space BCS-BEC crossover in FeSe monolayer
Superconductivity
2023-04-12 v1 Strongly Correlated Electrons
Abstract
The quantum many body states in the BCS-BEC crossover regime are of long-lasting interest. Here we report direct spectroscopic evidence of BCS-BEC crossover in real-space in a FeSe monolayer thin film by using spatially resolved scanning tunneling spectra. The crossover is driven by the shift of band structure relative to the Fermi level. The theoretical calculation based on a two-band model qualitatively reproduces the measured spectra in the whole crossover range. In addition, the Zeeman splitting of the quasi-particle states is found to be consistent with the characteristics of a condensate. Our work paves the way to study the exotic states of BCS-BEC crossover in a two-dimensional crystalline material at the atomic scale.
Keywords
Cite
@article{arxiv.2209.00758,
title = {Real-space BCS-BEC crossover in FeSe monolayer},
author = {Haicheng Lin and Wantong Huang and Gautam Rai and Yuguo Yin and Lianyi He and Qi-Kun Xue and Stephan Haas and Stefan Kettemann and Xi Chen and Shuai-Hua Ji},
journal= {arXiv preprint arXiv:2209.00758},
year = {2023}
}