Phase diagram and magnetization structures of spin-32 bond-alternating Ising chains with single-ion anisotropy

• Detailed magnetization structures of all the magnetization plateaus are uncovered.
• Some plateaus with the same magnetization have different spin configurations.
• Three D-h magnetization diagrams and phase diagrams are determined.
• Phase boundaries can be exactly determined by energy level crossing.
• A phase transition line (D=J) not recognized previously is detected.

By the infinite time-evolving block decimation (iTEBD) algorithm, the magnetization process of the spin-32 bond-alternating Ising chain with single-ion anisotropy (D) is investigated. Magnetization plateaus including detailed magnetization structures of three different cases are uncovered, and three rich ground-state phase diagrams are explicitly determined. Especially, for the uniform antiferromagnetic case, a phase transition line at D=J, which divides the Mz=0 (Mz=12) plateau into two phases, are detected by the magnetization structure and the ground-state energy, and a updated phase diagram is proposed. Such a transition line was not recognized by the average magnetization previously. A same transition line (D=J  ) is also detected in the phase diagram of the antiferromagnetic-ferromagnetic alternating case. Magnetization plateaus are found to be easily induced for the classical Ising systems without quantum fluctuations, and the single-ion anisotropy plays a key role in the formation of Mz=12 and 1 plateaus in the present model.