9 papers
Distinguishing Mott and strain-induced anisotropic semimetals in magic-angle twisted bilayer graphene using Landau level spectroscopy
Keshav Singh, Juan Felipe Mendez-Valderrama, Erez Berg +2
Recent quantum twisting microscopy experiments [1] have provided unprecedented momentum- and energy-resolved imaging of magic-angle twisted bilayer graphene, revealing a stark dich…
Extracting the full conductivity tensor in a rectangular sample
Julia Gelfond, Oskar Vafek
Electrical transport measurements reveal that many 2D materials exhibit anisotropic conductivity. However, current methodologies for rectangular geometries can only extract a parti…
Ferromagnetism vs. Antiferromagnetism in Narrow-Band Systems: Competition Between Quantum Geometry and Band Dispersion
Haoyu Hu, Oskar Vafek, Kristjan Haule +1
Magnetism in narrow-band systems arises from the interplay between electronic correlations, quantum geometry, and band dispersion. In particular, both ferro and anti-ferro magnets…
Visualizing Symmetry Broken Chern Insulators and their Quantum Melting
Minhao He, Yen-Chen Tsui, Ran Peng +4
In the presence of a magnetic field, electronic states of moiré quantum materials develop a Hofstadter spectrum that provides a unique setting for studying the interplay between b…
Orbital magnetization and magnetic susceptibility of interacting electrons
Jian Kang, Minxuan Wang, Oskar Vafek
We present a rigorous derivation of the orbital magnetization for interacting electrons within the self-consistent Hartree-Fock approximation. Our method also allows us to derive f…
Extended Fractional Chern Insulators Near Half Flux in Twisted Bilayer Graphene Above the Magic Angle
Joe Finney, Aaron L. Sharpe, Linsey K. Rodenbach +7
Fractional Chern insulators (FCIs) -- the lattice analog of fractional quantum Hall states -- form as fractionalized quasiparticles emerge in a partially-filled Chern band. This fr…