Spontaneous ordering of electronic spins below the Curie temperature, driven by exchange interaction. Heisenberg Hamiltonian H = −J Σ S_i·S_j; Weiss molecular field.
Spontaneous ordering of electronic spins below the Curie temperature, driven by exchange interaction. Heisenberg Hamiltonian H = −J Σ S_i·S_j; Weiss molecular field.