Hierarchical mean-field approach to the $J_1$-$J_2$ Heisenberg model on a square lattice

L. Isaev, G. Ortiz, J. Dukelsky

We study the quantum phase diagram and excitation spectrum of the frustrated $J_1$-$J_2$ spin-1/2 Heisenberg Hamiltonian. A hierarchical mean-field approach, at the heart of which…