Tuning the electronic structure of 2d materials via defect engineering and twisting

26/03/2019 @ 11:00 AM – 12:30 PM Asia/Singapore Timezone
S16 Level 6 – Theory Common Conference Room
Level 6, 6 Science Drive 2
Singapore 117546

Speaker: Dr. Johannes Lischner
Affiliation: Department of Materials Imperial College London
Host: Assist. Prof. Lu Jiong
Location: Click HERE for directions

Abstract Details: I will discuss two approaches for modifying the electronic structure of 2d materials. First, I will show how charged defects give rise to shallow bound states in semiconducting transition-metal dichalcogenides. Interestingly, the character of the lowest-lying impurity states depends sensitively on the defect charge – both its sign and magnitude. Then, I will discuss twisted bilayer graphene which has attracted considerable attention in recent months because of the experimental observation of significant electron correlation effects and even unconventional superconductivity. These findings are explained using advanced electronic structure methods based on the renormalization group.

About the Speaker: I am a Lecturer in the Department of Materials and a Royal Society University Research Fellow in the Department of Materials and the Department of Physics at Imperial College London. I am also the Assistant Director of the Centre for Doctoral Training in Theory and Simulation of Materials at Imperial College. I obtained a Ph.D. in physics from Cornell University in 2010 working in the group of Prof. Tomas Arias. From 2010 to 2014, I was a postdoctoral researcher at UC Berkeley and Lawrence Berkeley National Lab in the groups of Prof. Steven Louie and Prof. Marvin Cohen.