4 papers
Fluctuation-driven chiral ferromagnetism
Rokas Veitas, Ahmed Khalifa, Francisco Machado +1
Quantum fluctuations are often suppressed in ferromagnetic materials because they admit a simple unfrustrated ground state, greatly limiting the scope of the phenomena that can be…
Ground states of quantum XY dipoles on the Archimedean lattices
Marcus Bintz, Ahmed Khalifa, Vincent S. Liu +4
We report numerical ground states for the dipolar XY spin model, which describes extended antiferromagnetic interactions in two-dimensional arrays of polar molecules and two-level…
Direct visualization of gate-tunable flat bands in twisted double bilayer graphene
Souvik Sasmal, Ryan Muzzio, Ahmed Khalifa +12
The symmetry-broken correlated states in twisted double bilayer graphene (TDBG) can be tuned via several external knobs, including twist angle, displacement field, and carrier dens…
Strong Correlation Driven Quadrupolar to Dipolar Exciton Transitions in a Trilayer Moiré Superlattice
Yuze Meng, Lei Ma, Li Yan +13
The additional layer degree of freedom in trilayer moiré superlattices of transition metal dichalcogenides enables the emergence of novel excitonic species, such as quadrupolar ex…