Magnetization plateaus of an exactly solvable spin-1 Ising–Heisenberg diamond chain

The spin-1 Ising–Heisenberg diamond chain in a magnetic field is exactly solved by a rigorous treatment based on the transfer-matrix method. An exact ground-state phase diagram includes in total three unconventional quantum ground states with a quantum entanglement of the decorating spin-1 Heisenberg dimers apart from two ground states with a classical spin arrangement. It is evidenced that all three values of the magnetization allowed for the spin-1 diamond chain without translationally broken symmetry by the Oshikawa–Yamanaka–Affleck criterion can become evident in an outstanding stepwise magnetization curve with three intermediate plateaus at zero, one-third, and two-thirds of the saturation magnetization.