Apr 9, 2025
2:00pm - 2:30pm
Summit, Level 4, Room 443
Zhehao Ge1,Zehao He1,Qize Li1,Ziyu Xiang1,Jianghan Xiao1,Wenjie Zhou1,Mit Naik1,Salman Kahn1,Renee Sailus2,Rounak Banerjee2,Takashi Taniguchi3,Kenji Watanabe3,Sefaattin Tongay2,Steven Louie1,Feng Wang1,Michael Crommie1
University of California, Berkeley1,Arizona State University2,National Institute for Materials Science3
Zhehao Ge1,Zehao He1,Qize Li1,Ziyu Xiang1,Jianghan Xiao1,Wenjie Zhou1,Mit Naik1,Salman Kahn1,Renee Sailus2,Rounak Banerjee2,Takashi Taniguchi3,Kenji Watanabe3,Sefaattin Tongay2,Steven Louie1,Feng Wang1,Michael Crommie1
University of California, Berkeley1,Arizona State University2,National Institute for Materials Science3
Understanding electronic systems with both strong electron-electron interactions and electron-disorder interactions is challenging. In a pure low-density two-dimensional (2D) electronic system, it is well known that electrons form a Wigner crystal (WC) when the ratio (r
s) between electron-electron Coulomb repulsion energy and electron kinetic energy exceeds ~38. However, in real materials, defects and impurities that act as quenched disorder potentials are always present, which can alter the behavior of low-density 2D electronic systems compared to their disorder-free limit. For example, it is predicted that quenched disorders can distort the triangular lattice of a pure 2D WC and reduce the critial r
s for the transition of electrons from a liquid state to a solid state due to their pinning effect. Despite these predictions, microscopic characterization of the effects of quenched disorders on electron WCs remains limited. Here, I will present our recent results on the scanning tunneling microscope (STM) study of disordered electron WCs in gate-tunable bilayer MoSe
2 devices. In our experiments, MoSe
2 atomic defects that act as different types of disorder potentials, such as repulsive versus attractive and long-range versus short-range, were identified. The impact of these different types of disorder potentials on the wavefunction and quantum melting behavior of disordered electron WCs will be discussed in this talk.