5 papers
The "good" Boussinesq equation on the half-line: a Riemann-Hilbert approach
Christophe Charlier, Jonatan Lenells
We consider the ``good" Boussinesq equation on the half-line. Assuming existence of the solution, we prove that it can be recovered from the solution of a Riemann-Hilbe…
On the Hartree-Fock phase diagram for the two-dimensional Hubbard model
Christophe Charlier, Edwin Langmann, Jonatan Lenells
We propose an analytical method for the construction of Hartree-Fock phase diagrams for the (fermion) Hubbard model and various generalizations thereof. Such phase diagrams are tra…
On the mean-field antiferromagnetic gap for the half-filled 2D Hubbard model at zero temperature
Edwin Langmann, Jonatan Lenells
We consider the antiferromagnetic gap for the half-filled two-dimensional (2D) Hubbard model (on a square lattice) at zero temperature in Hartree-Fock theory. It was conjectured by…
Update of Hartree--Fock theory for Hubbard-like models
E. Langmann, J. Lenells
We show that the standard textbook description of (restricted) Hartree--Fock theory for (Fermi) Hubbard-like models is in need of an update, and we present such an update allowing…
Mixed phases in a Fermi--Hubbard model describing altermagnetism
E. Langmann, J. Lenells
We study an extension of the 2D Fermi--Hubbard model, which was recently introduced in [Das et al., Phys. Rev. Lett. 132, 263402 (2024)] and shown to describe altermagnetism that c…