Sylvain Capponi : Variational study of magnetization plateaus in the spin-1/2 kagome Heisenberg antiferromagnet

Sylvain Capponi, LPT Toulouse

“Variational study of magnetization plateaus in the spin-1/2 kagome Heisenberg antiferromagnet”

Contact: andrej.meszaros@universite-paris-saclay.fr

Le résumé :

We analyze the magnetization curve of the spin-1/2 kagome Heisenberg model in a magnetic field. Using state-of-the-art variational wavefunctions based on neural networks, we confirm the presence of robust magnetization plateaus at m=1/3, 5/9 and 7/9 of the saturation value, stabilized by a spontaneous symmetry breaking of lattice translations with a David-star unit cell.
Regarding the more challenging m=1/9 plateau, we find two competing valence bond crystals depending on the system size, both breaking translation as well as point group symmetries and with a larger 3×3 unit cell.

Reference: Andreas Raikos, Sylvain Capponi, Fabien Alet, arXiv:2602.12998